ATHENS, GREECE -- Ukrainian President Volodymyr Zelenskyy flew to Greece on Monday for talks with the country's leadership and to attend an informal meeting of Balkan leaders with top European Union officials.

Zelenskyy met with Greek Prime Minister Kyriakos Mitsotakis and was scheduled to meet with the figurehead president, Katerina Sakellaropoulou.

In the evening, Zelenskyy was to join an informal dinner organized by Mitsotakis for top officials from nine Balkan nations, European Commission President Ursula von der Leyen and European Council head Charles Michel, Mitsotakis' office said.

The dinner was scheduled to discuss the Western Balkans region's future in the EU, which many countries have already joined and the rest are jockeying to enter.

Greece has joined its NATO and EU partners in strongly backing Ukraine against the Russian invasion and has provided military assistance in the form of armored personnel carriers and ammunition.

But Athens has resisted pressure to provide Kyiv with a Russian-made air defense missile system stationed on the southern island of Crete. Greece is engaged in a substantial weapons procurement program of its own amid testy relations with neighboring Turkey -- its NATO ally and historic regional rival.

Earlier Monday, Zelenskyy was in Denmark, where he thanked lawmakers for helping his country resist Russia's invasion. On Sunday, Denmark and the Netherlands announced they would provide Kyiv with F-16 warplanes that could be delivered around the end of the year.

The Athens dinner was being hosted on the 20th anniversary of an EU-Western Balkan summit in the northern Greek city of Thessaloniki as Balkan states sought to join the bloc.

The presidents of Serbia, Montenegro and Moldova, the prime ministers of North Macedonia, Kosovo, Bulgaria, Croatia and Romania, and the head of the council of ministers of Bosnia and Herzegovina were to attend Monday's dinner. Mitsotakis was also meeting several of them individually on Monday and Tuesday.

A notable absence was Albanian Prime Minister Edi Rama. Relations between Greece and its northwestern neighbor have soured over the jailing of ethnic Greek minority leader Fredi Beleri, who was arrested before local elections in May on vote-buying allegations.

Beleri was elected mayor of the southwestern Albanian town of Himara despite being in pre-trial detention. Athens insists his detention is politically motivated and has called for his release.

"I believe we all understand that it was not possible to invite Mr. Rama to such an important initiative," Greek government spokesperson Pavlos Marinakis said.

"When we say that Albania's European path passes through the basic respect of European rules and the rules of justice, we mean it," he added, noting that Albania's president had declined an invitation to attend.