The Manhattan district attorney's office will no longer prosecute arrests for prostitution or unlicensed massage in a new, formal policy that may be a first for New York, DA Cy Vance said Wednesday.

Vance's office also dismissed more than 900 open cases for those offenses, dating back to the 1970s, as well has more than 5,000 cases tied to the now-repealed "loitering for the purpose of prostitution" statute.

“For years, rather than seeking criminal convictions, my Office has reformed its practice to offer services to individuals arrested for prostitution. Now, we will decline to prosecute these arrests outright, providing services and supports solely on a voluntary basis," Vance said in a statement.

While the office had, since 2016, not prosecuted prostitution cases if the defendant went through mandatory counseling, under the new policy all offers of services will be voluntary and all charges dismissed by the office's Human Trafficking Response Unit.

Vance's office said it believes the "Decline-to-Prosecute Policy" is the first of its kind in the state.

Other DAs have, however, made similar moves to close the books on old cases. Brooklyn DA Eric Gonzalez moved to dismiss more than 1,000 prostitution cases earlier this year; he has also previously called for Albany to decriminalize sex work.