The International Atomic Energy Agency (IAEA) said Friday that it was informed by Ukrainian authorities that the country's nuclear power reactors are continuing to "operate safely and securely."

Regarding reports of higher radiation levels at the site of the Chernobyl nuclear power plant, the IAEA has assessed that the readings reported by Ukraine's regulatory authority are "low and remain within the operational range" and "do not pose any danger to the public," IAEA Director General Rafael Mariano Grossi said in a statement.

The IAEA was informed by the Ukrainian authorities that the higher radiation levels may have been caused by heavy military vehicles stirring up soil still contaminated from the 1986 Chernobyl accident.

Ukraine told the IAEA on Thursday that "unidentified armed forces" had taken control of the Chernobyl plant, according to the statement.

Interfax-Ukraine news agency on Thursday quoted Advisor to head of the President's Office of Ukraine Mykhailo Podoliak as saying Russian forces had seized the Chernobyl plant.

Grossi on Friday reiterated his appeal for maximum restraint to avoid any action that could jeopardize the safety of nuclear facilities in Ukraine.