ANTALYA, Turkey -- The chief of the International Atomic Energy Agency (IAEA) on Thursday held meetings with Ukrainian and Russian foreign ministers respectively on nuclear security in a town in Turkey's southern province of Antalya, Turkish official sources said Friday.

At the invitation of Turkish Foreign Minister Mevlut Cavusoglu, IAEA Director General Rafael Mariano Grossi arrived in Belek, a town about 30 km from Antalya's provincial capital, to attend the Antalya Diplomatic Forum that kicked off on Friday, the sources said.

On the sidelines of the international forum, Grossi held separate meetings with Ukrainian Foreign Minister Dmytro Kuleba and Russian Foreign Minister Sergey Lavrov, a source of the Turkish Foreign Ministry told Xinhua.

Following the talks, Grossi wrote in two successive tweets that his meeting with Kuleba was "important and forward-looking," and that with Lavrov was "constructive and important."

"We are making progress on the safety and security of nuclear facilities in Ukraine," he wrote.

Both Kuleba and the Permanent Mission of Russia to the International Organizations in Vienna confirmed via Twitter that safety and security of nuclear facilities in Ukraine were discussed in the meetings.

Lavrov and Kuleba held a meeting on Thursday in Belek in the presence of Cavusoglu, the first high-level meeting between Moscow and Kyiv since Russia's special military operation in Ukraine started on Feb 24.

During the meeting, the two sides failed to make progress on a ceasefire but agreed to continue negotiations over the conflict.