The European Commission has given Turkey until mid-December to open its ports to ships from Cyprus or face unspecified consequences.
Turkey has failed to open its ports to Cypriot trade, despite signing a protocol last year extending a customs deal to all 25 members of the enlarged EU.
The Commission said in a report on Turkey's progress towards membership of the Union that it would make relevant recommendations ahead of the December EU summit if Ankara has not fulfilled its obligations.
The report also said Turkey must do more to bolster freedom of expression, to protect the rights of women and ethnic and religious minorities and to rein in the powerful military.
The Commission did not recommend any slowing or freezing of EU membership negotiations with Ankara.
Attempts by Finland to convene a meeting between the parties to seek a resolution of the deadlock failed late last month.
Slow progress on other candidates
The Commission issued mixed reports on seven other candidate or aspirant countries, recommending no dramatic step forward with any of them.
EU Enlargement Commissioner Olli Rehn said EU expansion was not an express but 'a slow, slow train coming and not precisely up around the bend'.
The Commission pressed Croatia, the other candidate already in negotiations, to fight corruption harder, reform its judiciary and administration and speed economic reforms.
It also said there is no prospect of another simultaneous wave of expansion like the 2004 'big bang', when 10 mostly ex-communist countries joined.