The head of the UN’s nuclear energy watchdog has offered to travel to Ukraine in a bid to broker a deal with Russia and avoid further damage to radioactive power plants during the conflict.

Rafael Mariano Grossi, director-general of the United Nations’ International Atomic Energy Agency (IAEA), said he has volunteered to travel to Chernobyl – the site of a nuclear disaster in the 1980s and now under Russian control since the invasion started – to reach a “framework” to uphold nuclear safety.

In a move condemned by Western leaders, Russian forces shelled the power station in the city of Zaporizhzhia overnight, with the attack continuing even as emergency services tried to put out the resulting fire.

Mr Grossi said there has been no release of radiation at the nuclear plant – the largest of its kind in Europe – and that the radiation monitoring system is “fully functional”.

However, he said IAEA members are in an “unprecedented” situation following the damage, and that the industry is in “completely uncharted waters”.

A Russian “projectile” struck a training centre on the site but the building that was hit was not part of the reactor, he told reporters at a press conference.

In the aftermath of the attack, Mr Grossi said he had proposed to both Kyiv and Moscow that he meet political delegates to ensure key “principles” of nuclear safety are upheld during the fighting.

Austria Nuclear Russia Ukraine War
IAEA director-general Rafael Mariano Grossi has offered to broker a deal between Ukraine and Russia (Lisa Leutner/AP)

He said one of the seven principles for the safe use of nuclear energy – to ensure the “physical integrity” of a power plant – has been “compromised with what happened last night” in Zaporizhzhia.

He said it was “fortunate” there was no radiation release on this occasion and it “could have been dramatic”.

“Bearing in mind what is happening and the risks that we may all incur if this continues without an enhancement and without recommitment to these principles, I have indicated to both the Russian Federation and the Ukraine my availability and disposition to travel to Chernobyl as soon as possible so that these seven crucial pillars are never again compromised,” he said.

“The idea behind this initiative of mine as director-general of IAEA is to agree on a framework and compromise that would commit to not compromising these principles which we all subscribe and agree to.

“We all know that, given the very complicated circumstances on the ground, the logistics for such a trip, my presence in this place is not going to be easy, but at the same time I believe it wouldn’t be impossible.”

Speaking from the organisation’s headquarters in Vienna, Austria, Mr Grossi said both sides are “considering” his offer to travel to Chernobyl.

Reactor number four at the Chernobyl plant exploded and caught fire in 1986, shattering the building and spewing radioactive material high into the sky.

Even 36 years later, radioactivity is still leaking from history’s worst nuclear disaster.

Offering a further update on what happened at Zaporizhzhia, Mr Grossi said two people on the site were injured in the blaze.

He said that only one reactor is operating at about 60% and it continues to be controlled by Ukrainian technicians.

In an update posted on social media after the briefing, the IAEA said Ukrainian officials had informed the watchdog that Russian forces had taken control of the Zaporizhzhia plant but that the safety systems of the site’s six reactors have not been affected.