The Foreign Secretary is to condemn Moscow’s atrocities in Ukraine when he meets his Russian counterpart for the first time.

James Cleverly will face Sergei Lavrov on Thursday during a special meeting of the United Nations Security Council, where foreign ministers are due to discuss the war.

World leaders and senior diplomats from across the globe are gathered at the UN General Assembly in New York this week, with Mr Cleverly attending as part of a UK delegation headed by Liz Truss – his first overseas trip since taking the role.

Every day, the devastating consequences of Russia’s invasion become more clear and evidence of Russian atrocities continues to mount

Global affairs continue to be overshadowed by the Ukraine conflict, which threatened to spiral into a nuclear crisis as Vladimir Putin warned that Russia would use “all the means at our disposal” to protect itself.

In a speech on Wednesday, the Russian president also announced a partial military mobilisation as the Kremlin attempts to regain ground in the face of a counterattack by Ukraine’s forces.

At the Security Council meeting, Mr Cleverly will commit to working with allies on holding Russia accountable and seeking justice for victims.

He is expected to say: “Ukrainians’ resilience and spirit of defiance, in defence of their country, continues to inspire all free people and nations.

“But every day, the devastating consequences of Russia’s invasion become more clear and evidence of Russian atrocities continues to mount.

“We can and must make clear to President Putin that his attacks on the sovereign will of the Ukrainian people – so clearly expressed as they fight for their homes – must stop, his assaults on the UN charter and international norms that protect us will not be tolerated, and that he must withdraw from Ukraine to enable a return to regional and global stability.”

The Foreign Secretary will also argue that Moscow plans to fix the results of referendums on becoming parts of Russia due to be held in Russian-controlled regions in eastern and southern Ukraine.

Russia is outnumbered on the Security Council, but wields a veto.

Later on Thursday, Mr Cleverly will join a meeting focused on accountability for war crimes in Ukraine.

The Foreign Secretary and US secretary of state Antony Blinken both stressed unwavering support to Kyiv and to “maintaining unity with partners to ensure Putin fails in his illegal war” when they met at the UN gathering on Tuesday, according to a read-out of the encounter.

Mr Cleverly also had a meeting with Ukrainian foreign minister Dmytro Kuleba.

In her summit speech, Ms Truss pledged that the UK under her leadership would work with allies to counter authoritarianism and champion freedom, sovereignty and democracy.

The Prime Minister met Ukrainian first lady Olena Zelenska and prime minister Denys Shmyal to tour an exhibition titled Russian Warcrimes at the Ukrainian Institute of America on Tuesday.