Russian leader Vladimir Putin has said UN officials will be granted permission to visit and inspect the Zaporizhzhia nuclear complex.
The Kremlin made the announcement after a call between Mr Putin and French President Emmanuel Macron.
It came after UN chief Antonio Guterres told the BBC that he is “concerned” about the situation at the plant.
He said military activity around Zaporizhzhia must end and urged Moscow to grant access to inspectors.
The site has been under Russian occupation since early March but Ukrainian technicians still operate it under Russian direction.
In a readout following the call between the French and Russian leaders, the Kremlin said Mr Putin had agreed to provide UN investigators with “the necessary assistance” to access the site.
“Both leaders noted the importance” of sending the IAEA experts to the plant for an assessment of “the situation on the ground,” the Kremlin said.
The director-general of the UN’s nuclear watchdog, the International Atomic Energy Agency (IAEA), welcomed Mr Putin’s statement, and said he was willing to lead a visit to the plant himself.
“In this highly volatile and fragile situation, it is of vital importance that no new action is taken that could further endanger the safety and security of one of the world’s largest nuclear power plants,” Rafael Grossi said.
Ukrainian officials say Russia has turned the complex into an army base – deploying military equipment, weapons and about 500 troops who are using the site as a shield to attack towns across the Dnieper River.
And in recent weeks the area around the facility has come under heavy artillery fire, with Kyiv and Moscow blaming each other for the attacks.
On Thursday, during a meeting with Mr Guterres and Turkish leader Recep Tayyip Erdogan, Ukrainian President Volodymyr Zelensky criticised “deliberate” Russian attacks on the power plant.
Despite displaying some willingness to grant access to inspectors, Russian officials have flatly refused international demands to demilitarise the site.
Ivan Nechayev, deputy director of the Russian foreign ministry’s information and press department, said on Friday that such moves would leave the plant “even more vulnerable”.
Meanwhile, Russia submitted a letter to the UN Security Council detailing the “provocations” that it accuses Ukraine of plotting at the Zaporizhzhia nuclear power plant.
The Russian mission to the UN alleged that the Ukrainians want to cause “what they believe to be a minor accident”, consisting of a radiation leak, which could see Russia accused of “nuclear terrorism”.
The letter denied that Russian troops are storing weapons on site. It repeated an allegation that the Ukrainians have been shelling the plant.