This was CNBC's live blog tracking developments on the war in Ukraine.

The largest exchange of prisoners of war since the start of the Russia-Ukraine war took place on Wednesday, prompting hopes that POW swaps will continue after they stalled last summer.

Confirming the exchange, Russia said it received 248 prisoners of war from Ukraine, while Ukraine said it got 230 of its military personnel and captured civilians back. According to the Russian Ministry of Defense, the prisoner exchange came about with mediation from the United Arab Emirates.  

The exchange comes after prisoner exchanges stalled at the end of last summer, leading to regular protests by the families of POWs who demanded the exchanges resume. Many families have not heard from their loved ones since they were captured by Russia early on in the war.

Commenting on the latest exchange, Ukraine's President Volodymyr Zelenskyy said "our people are home."

"More than 200 of our soldiers and civilians were returned from Russian captivity. Soldiers, sergeants, officers. Soldiers of the Armed Forces, National Guard, Navy, border guards. Part of the defenders defended Mariupol and Azovstal," he said on Telegram Wednesday.

In other news, Ukraine's Foreign Minister Dmytro Kuleba said there is no "plan B" for Ukraine, adding that Kyiv is confident it can win the war against Russia with the military resources available to it.

Russia destroys Ukrainian missiles over Crimea

Russian air defense systems blocked an attack on Crimea on Thursday, the Russian Defense Ministry said in a Telegram post. Ten Ukrainian missiles were destroyed over the occupied peninsula, the post said.

CNBC was not able to independently verify the reports.

It comes after reports of attacks from Ukraine on Russian-occupied Crimea earlier in the week as a series of retaliatory strikes between the countries intensified.

— Sophie Kiderlin

Putin offers citizenship to foreigners who fight for Russia

President Vladimir Putin issued a decree on Thursday allowing foreign nationals who fight for Russia in Ukraine to obtain Russian citizenship for themselves and their families.

The order said people who have signed contracts during what Moscow calls its "special military operation" in Ukraine can apply to get Russian passports for themselves and their spouses, children and parents.

They must provide documents showing that they signed up for a minimum of one year.

Those eligible include people who have signed contracts with the regular armed forces or other "military formations" - a description that could apply to groups such as the Wagner mercenary organisation.

The measure appeared to be aimed at creating additional incentives for foreigners with military experience to apply to join Russian ranks.

Moscow does not publish data on the number of foreigners fighting on its side in Ukraine. However, Reuters has reported previously on Cubans who signed up for the military in return for bonuses equivalent to more than 100 times the average Cuban monthly salary, and three Africans recruited by Wagner, of whom two were killed in action.

— Reuters

One dead, eight wounded in Russian missile strike on central Ukraine

One civilian was killed and eight others were wounded on Thursday in a missile strike on the central Ukrainian town of Kropyvnytskyi, regional governor Andriy Raikovych said in a briefing, according to Reuters. Russia had likely used an X-59 missile for the attack, he said.

In a post on Telegram, Raikovych said that those who were injured all have shrapnel wounds. The regional hospital responded quickly and doctors are taking care of those who require inpatient care, he added.

The strike also led to power and water cuts in parts of Kropyvnytskyi, the governor said according to Reuters, but services have been restored.

CNBC was unable to independently verify the reports.

— Sophie Kiderlin

Russia goes ahead with plans to buy Iranian ballistic missiles — WSJ

Russia is planning to buy short-range ballistic missiles from Iran, a step that would enhance Moscow's ability to target Ukraine's infrastructure, the Wall Street Journal reported on Thursday, citing U.S. officials.

Last year, the White House said it was seeing more indications that Russia and Iran were expanding an unprecedented defence partnership that would help Moscow prolong its war in Ukraine as well as pose a threat to Iran's neighbours.

— Reuters

NATO to hold new Ukraine Council meeting on Jan. 10

NATO chief Jens Stoltenberg will convene a meeting between NATO diplomats and officials from Ukraine on Jan. 10, following a recent wave of heavy Russian air strikes on the country, the transatlantic defense alliance said on Thursday.

The meeting, taking the format of the newly establish NATO-Ukraine Council, was being convened at Kyiv's request following missile and drone attacks on Ukrainian civilians, cities and towns, a NATO spokesperson said.

Russia has intensified attacks over the New Year period, with President Vladimir Putin warning that a Ukrainian air strike on the Russian city of Belgorod, which Moscow said killed 25 civilians, would "not go unpunished".

— Reuters

IAEA says denied access to parts of Russia-controlled power station

The head of the U.N. nuclear power watchdog said on Wednesday his inspectors had been denied access to parts of Ukraine's Russian-occupied Zaporizhzhia nuclear power station and had yet to receive 2024 maintenance plans for the facility.

The Zaporizhzhia plant was seized by Russia in the days following Moscow's 2022 invasion of Ukraine. Each side has accused the other of shelling around the station, Europe's largest, though its six reactors now produce no electricity.

Rafael Grossi, Director General of the International Atomic Energy Agency, said inspectors at the plant had for two weeks had no access to the main halls of reactors one, two and six.

"This is the first time that IAEA experts have not been granted access to a reactor hall of a unit that was in cold shutdown," Grossi said in a statement on the IAEA website.

"This is where the reactor core and spent fuel are located. The team will continue to request this access."

Inspectors had also been restricted in their access to turbine halls at the plant in southeastern Ukraine, he said.

Grossi said the plant's operators had taken action to ensure back-up electricity supplies to the facility for instances when its main external power line is lost, which he described as a "repeated" occurrence.

— Reuters

No 'plan B' for Ukraine, foreign minister says

Ukraine's Foreign Minister Dmytro Kuleba said there is no "plan B" for Ukraine, saying Kyiv is confident it can win the war against Russia with the resources available to it.

"We don't have a plan B. We're confident in plan A," Kuleba told CNN's Christiane Amanpour Wednesday when asked whether Kyiv was prepared for a potential decrease or shortfall in Western military assistance given increasing political wrangling over continuing aid packages, particularly in the U.S.

"Ukraine will always fight with the resources available to it ..and what is given to Ukraine is not charity, it's an investment in the protection of NATO and the protection of the prosperity of the American people," Kuleba said.

— Holly Ellyatt

Russia, Ukraine exchange prisoners of war

Russia and Ukraine said on Wednesday that prisoners of war had been exchanged between the countries.

Over 200 "warriors and civilians" had been returned, Ukrainian President Volodymyr Zelenskyy said in a post on X, formerly Twitter.

That includes "soldiers, sergeants, and officers. Armed Forces, National Guard, Navy, and Border Guards. Some of the defenders fought in Mariupol and Azovstal," he said.

Russia's Defense Ministry said in a post on Telegram, according to a Google translation, that 248 Russian military personnel had been released after "a complex negotiation process."

The exchange was aided by the United Arab Emirates who provided "humanitarian mediation," the ministry added.

— Sophie Kiderlin

Ukraine 'grateful' for fighter jets sent by Norway to support pilot training

Ukraine's Ministry of Defense said it was "grateful" to Norway for supplying F-16 fighter jets to help train Ukrainian pilots.

"Norway is presenting two F-16 fighter jets that will train and educate Ukrainian personnel in Denmark," the ministry wrote in a post on X, formerly Twitter.

"We are grateful to our Norwegian friends for their unwavering support!"

Norway's Defense Minister confirmed earlier on Wednesday that the fighter jets would be donated{=null} for training purposes.

— Sophie Kiderlin

Polish farmers to resume blockade of Ukraine border crossing

Polish farmers will resume their blockade at the Medyka border crossing with Ukraine from Thursday as they say they have not received a signed assurance from the prime minister that their demands will be met, state-run news agency PAP reported.

The Polish farmers suspended their protest, which aims to secure government subsidies for corn and prevent tax hikes, on Dec. 24.

Polish truck drivers, however, have continued to block several crossings with Ukraine since Nov. 6, to press their demand that the European Union reinstate a system that requires Ukrainian companies to obtain permits to operate in the bloc. The same would apply to European truckers seeking to enter Ukraine.

"We have not received written confirmation that our demands will be met, so we are continuing the protest," farmers leader Roman Kondrow told PAP.

Although Agriculture Minister Czeslaw Siekierski had provided a note telling the farmers their demands would be met, Prime Minister Donald Tusk has not given a signed declaration, Kondrow said.

He added they would only allow one truck per hour pass through the crossing. Tusk said in December that he believed Poland was close to being able to end the truckers' protest.

— Reuters

The latest Russian missile attacks show a change in target, UK says

The latest missile attacks on Ukraine indicate that Russia is targeting Ukraine's defense industry rather than energy infrastructure, as seen last year.

"Since 29 December 2023, Russia has increased the intensity of its long-range strike operations against Ukraine," the U.K.'s Ministry of Defence said Wednesday.

It noted that Russian forces had committed a "significant proportion" of the stock of air-launched cruise missiles and ballistic missiles that they had built up in recent months to strikes on targets across Ukraine in the last week.

"The recent strikes likely primarily targeted Ukraine's defense industry. This contrasts with its major attacks last winter which prioritised striking Ukraine's energy infrastructure," the ministry noted in an intelligence update on X, formerly known as Twitter, Wednesday.

"These new operations suggest at least a temporary change in approach in Russia's use of long-range strikes. Russian planners almost certainly realise the importance of relative defence industrial capacity as they prepare for a long war."

— Holly Ellyatt

Read CNBC's previous live coverage here:

Ukraine attacks Russian city of Belgorod and occupied Crimea overnight as retaliatory strikes intensify