The European Union began negotiations Thursday on a new chapter under Turkey's membership bid, on financial and budgetary provisions, as agreed under a migration deal struck with Ankara.
Turkey has officially been a candidate for EU membership since 1999, but progress has been slow, hampered by years of opposition from France and Germany, as well as geopolitical tensions over Cyprus.
Turkey demanded progress on its membership bid in exchange for its help in stemming migrant flows to Europe. The migration agreement struck by the two sides in March foresaw a new negotiating chapter being opened before July.
As part of the EU accession process, negotiations have to be conducted on 35 chapters, which each cover a policy area in which Ankara must meet EU standards.
The chapter opened Thursday covers financial contributions to the EU's budget.
It requires Turkey to develop the "appropriate administrative capacity to adequately co-ordinate and ensure the correct calculation, collection, payment and control" of budget contributions, the EU said in a statement.
It is the 16th accession chapter to be opened in Turkey's membership negotiations, although the most sensitive topics - for instance justice, security and fundamental rights - have so far been avoided.
Negotiations have been concluded on just one of the 16 chapters, on science and research.
The prospect of closer ties between the EU and Turkey has proven controversial, amid concerns about Ankara's human rights record and the authoritarian behaviour of President Recep Tayyip Erdogan.