European Union officials say leaders of the 25 EU countries, opening a two-day summit in Brussels Thursday, will slow down the block's further expansion as they seek to fully integrate the 10 members that joined in 2004.
EU enlargement commissioner Olli Rehn told the European Parliament the union must maintain its enlargement momentum, but stressed that candidate countries must meet rigorous entry requirements.
Romania and Bulgaria are to formally gain EU entry New Year's Day. Other candidates, including Croatia, Macedonia and Turkey, will have to wait longer.
The leaders are expected to approve the decision of the block's foreign ministers to partially suspend membership negotiations with Turkey in response to that country's failure to normalize trade with Cyprus.
A Turkish Foreign Ministry spokesman criticized the EU action as unjust and as a surrender to Greek Cypriot pressure.
Turkey agreed last year to extend its EU customs agreement to 10 countries, including Cyprus, that joined the bloc in 2004. But it has failed to open its ports and airports to ships and planes from Cyprus, under its internationally-recognized Greek Cypriot led government.
Turkey insists there should be no link between its EU membership bid and resolution of the division of Cyprus. Ankara has pledged to open its ports to Cyprus if EU officials end the isolation of the Turkish Cypriots.
Cyprus has been divided since 1974, when Turkish troops invaded the island in response to a coup in Nicosia backed by the military government then in power in Greece.
Some information for this report was provided AFP, AP and Reuters.