"Turkey's initiative is a positive step ... but still needs clarification," Finland's Foreign Minister Erkki Tuomioja, whose country holds the rotating EU presidency, said in a statement.
Tuomioja said that if Ankara was ready "for such an unconditional move," it would influence an EU decision next week on whether to partially freeze membership talks.
Finnish officials in Helsinki said talks were ongoing between Helsinki and Ankara on clarifying Turkey's offer and EU ambassadors would analyze the plan on Friday.
It was doubtful whether Turkey's plan -- which EU officials said would allow Greek Cypriot ships to use one Turkish port -- would be enough to persuade every EU country not to push for a partial freeze on the EU's membership talks with Turkey.
EU foreign ministers are meeting in Brussels on Monday and will discuss the issue ahead of a Dec. 14-15 EU summit.
Turkey signed an agreement in 2005 to open its ports and airports to 10 new EU members -- which included Cyprus. But it has refused to receive goods from Cyprus, which remains divided between an internationally recognized Greek Cypriot government in the south and an isolated Turkish Cypriot breakaway state in the north. The northern part of the island has been under a crippling trade embargo.
EU members Greece and Cyprus have insisted that Turkey must abide by the agreement and open all its ports and airports to the Greek Cypriots.
Turkey's last-minute move to avert a partial suspension of EU membership talks immediately laid bare differences among EU capitals.
European Commission President Jose Manuel Barroso, reacting to earlier reports that Turkey would open several ports and airports, said its offer was "an important step" to ending the stalemate.
"If that move can be duly confirmed, I think it's certainly an important step," Barroso told reporters. "I certainly welcome that initiative."
But Greece, Cyprus' closest ally, warned that opening some -- but not all -- of Turkey's ports to Cyprus was not enough, and EU officials said privately that they looked to Turkey to "fully implement" the customs pact, meaning all ports and airports should be opened to Cyprus.
In an apparent hardening of its stance, Athens said the EU must send Ankara "a strong message" for refusing to fully comply with its promises to the bloc, reaction that indicated the issue will continue to divide the EU in the run-up to next week's summit.
EU leaders could decide at the summit to partially suspend EU membership talks with Turkey.
Britain, Spain and Sweden have indicated that suspending parts of Turkey's membership negotiations was too harsh and would damage ties with Ankara. But France, Cyprus and Greece are demanding a harder line against Turkey. They have blocked negotiations with Ankara since September in protest over the country's refusal to extend the customs union to Cyprus.
Turkish news reports had earlier said that said Ankara proposed to open two seaports temporarily and unconditionally to Cyprus -- but would only open a Turkish airport in return for trade to the Turkish Cypriot state in the north.
Barroso said the Commission was ready to end the embargo on the Turkish Cypriots.
"We are still a long way from an ideal situation but we are very much in favor of breaking the isolation in the northern part of Cyprus," he said.
In Berlin, Germany's Foreign Minister Frank-Walter Steinmeier said "Turkey appears to be cautiously prepared to make a concession."
Two weeks ago, Finland, which holds the rotating EU presidency, proposed reducing restrictions on the Turkish Cypriots if Turkey opened its ports to the Greek Cypriots. The plan would grant the northern Cyprus seaport of Famagusta free trade with the EU if the Turkish side hands over control of the nearby abandoned town of Varosha. Ankara rejected the proposal.
Cyprus has been divided since 1974, when Turkey invaded following a failed coup staged by supporters of union with Greece. Ankara is the only government to recognize the Turkish Cypriot state.
