Rishi Sunak held his first call with Volodymyr Zelensky on Tuesday, pledging the UK’s “steadfast support” for Ukraine.

Both his predecessors Boris Johnson and Liz Truss had vocally promised full support to the war-torn country and on Tuesday evening the new Prime Minister said the UK’s support would be as “strong as ever” under his leadership.

Calling it a “privilege” to speak to Mr Zelensky, who had earlier sent him congratulations, Mr Sunak tweeted: “Both he and the Ukrainian people can count on the UK’s continued solidarity and support.

“We will always stand with Ukraine.”

Mr Zelensky, in a tweet, called it an “excellent conversation” with the pair agreeing to “write a new chapter” in relations between the two countries.

Speaking outside Number 10 on Tuesday, the new Prime Minister referenced Russia’s invasion of Ukraine twice, saying: “Putin’s war in Ukraine has destabilised energy markets and supply chains the world over.”

A Downing Street spokesperson said the pair spoke on Tuesday evening “to underline the United Kingdom’s steadfast support for Ukraine”.

“The Prime Minister said the United Kingdom’s support for Ukraine would be as strong as ever under his premiership, and President Zelensky could count on his Government to stand in continued solidarity.

“The Prime Minister also noted the importance of the International Atomic Energy Agency’s work in Ukraine to ensure nuclear safety and provide transparency around any disinformation.

“Both leaders agreed on the need to continue to place pressure on Putin’s barbaric regime through continued economic sanctions.

“President Zelensky congratulated the Prime Minister on his appointment and wished him a happy Diwali. The Prime Minister thanked him and said he hoped they would see each other in person soon.”

In his congratulatory message to Mr Sunak earlier, French President Emmanuel Macron also said the two countries would work together to tackle the challenge of the war in Ukraine.

Ms Truss was widely criticised after she declined to say whether Mr Macron was a “friend or foe” when asked during the previous Tory leadership contest.

Mr Macron later suggested it was a “problem” if Britain could not call itself a friend of France.

Ms Truss eventually hailed the French President as a friend when the pair met at the first summit of the European Political Community in Prague.

In his message to Mr Sunak, Mr Macron tweeted: “Congratulations to Rishi Sunak, who has become Prime Minister of the United Kingdom.

“Together we will continue working to tackle the challenges of the moment, including the war in Ukraine and its many consequences for Europe and the world.”