The U.N. nuclear watchdog's 35-nation Board of governors will hold an emergency meeting on Wednesday on the Ukraine crisis.

According to Reuters, Canada and Poland called the meeting at the request of Ukraine, which is not on the Board.

International Atomic Energy Agency (IAEA) member states that are not on the Board, like Ukraine, can call a Board meeting but the possible range of topics is wider if a Board member calls one.

"The IAEA Board of Governors will hold a meeting on Wednesday to discuss the current situation in Ukraine," Reuters quotes the IAEA.

"The safety, security and safeguards implications of the situation in Ukraine," a diplomat said.

Earlier on Sunday, Ukrainian President Volodymyr Zelenskyy agreed to talks with Russia at the Belarusian-Ukrainian border. 

He had initially rejected a Russian offer of talks in Belarus, suggesting alternative cities including Budapest and Warsaw for talks.

As that developed, Russia warned Ukraine that it would not suspend military operations during any potential talks.