The offer came hours after Russian invasion forces seized control of Europe's largest power plant at Zaporizhzhia after a battle with Ukrainian troops that caused a fire and fears of an accident.

"I have indicated to both the Russian Federation and Ukraine my availability... to travel to Chernobyl as soon as possible," Rafael Grossi, director general of the International Atomic Energy Agency told reporters.

"Both sides are considering" the possibility, he added.

Grossi said the aim of the trip would to be to discuss with both sides a "framework" to safeguard the security and functioning of Ukraine's nuclear sites.

On February 24, Russia seized the site of the 1986 Chernobyl disaster, which left hundreds dead and spread radioactive contamination west across Europe.

Grossi said that any trip would take place after his return from Tehran on Saturday.

There he is due to hold talks with senior Iranian officials over outstanding questions the IAEA has about past nuclear activity at undeclared sites in Iran.