Some aspects regarding EU-Turkey visa-free regime still need to be negotiated, German Chancellor Angela Merkel said Thursday, February 2, according to Sputnik.

"Great job has been done on the way to visa-free regime, still some issues remain open, we need to work on them," Merkel told a joint press conference with Turkish Prime Minister Binali Yildirim.

In March 2016, Ankara and Brussels agreed on a migrant deal, under which Turkey pledged to take back all undocumented migrants who arrive in the European Union through its territory in exchange for Syrian refugees accommodated in Turkey. In return, the bloc pledged to accelerate the Turkish EU accession bid and introduce a visa-free regime, as well as provide financial aid to Turkey to cover the costs of migrant reception.

In November, the European Parliament voted in favor of freezing EU accession talks with Turkey over concerns about Ankara's post-coup crackdown. While the vote was non-binding and mostly symbolic, the move was widely criticized in Ankara.

Turkey signed an association agreement with the then-European Community in 1963, and submitted a membership application in 1987. Talks about Ankara's membership of the European Union began in 2005. The negotiations on Turkey's EU membership have been repeatedly suspended due to various obstacles.