Ukrainian President Volodymyr Zelenskyi thanked Serbian President Oleksandr Vucic on Wednesday for his support in the two-year war between Kyiv and Russia and promised to continue working on Kyiv’s plan to end the conflict, Reuters reported.

Vucic, who met with the Ukrainian leader at a summit of Southeast European countries in Albania, offered additional humanitarian aid and said he believed that “only constructive dialogue and diplomatic solutions can bring peace.”

Writing on Instagram, he also thanked Ukraine for being one of the few countries that refrains from recognizing the separatist Serbian province of Kosovo.

Zelensky, writing in X, formerly Twitter, “noted the importance of Serbia’s participation” in the implementation of Ukraine’s plan, which provides for the withdrawal of Russian troops and the restoration of the Soviet borders of Ukraine after 1991.

The two leaders also discussed “political and security challenges in Eastern Europe,” he said.

Last year, a classified Pentagon document said that Serbia had agreed to supply weapons to Kiev or had already sent them, despite its declared neutrality in the war with Ukraine. Serbia refused to impose sanctions against Russia, with which it has traditional ties.

In his comment, Vučić noted that it is necessary to take into account Serbia’s Slavic ties with Ukraine.

Ukraine’s refusal to recognize Kosovo, he said, made it “one of the few countries that can talk about territorial integrity, because it did not trample on someone’s territorial integrity like most others.”

Ukraine refused to recognize Kosovo’s independence from Serbia, which was declared in 2008, because it was dealing with separatist movements in Crimea and the east of the country before the current conflict began.