Former defence secretary Sir Ben Wallace has claimed that “momentum has dropped back” on Ukraine.

Sir Ben told the BBC that the UK’s leadership on Ukraine has “started to drop back into the… pack” and said that in order to drive change while in government “you have to really do it every single day”.

The former army officer – who served in the Ministry of Defence under the last three Conservative prime ministers – said that Britain’s stance had brought “lots of Europeans with us”.

His comments come amid uncertainty over the future of US backing for Kyiv after Donald Trump’s election victory this week

Sir Ben told Radio 4’s Today programme: “What has happened is the leadership that Britain showed right from the start has started to drop back into the sort of pack.”

He claimed that officials during his time in government had been reluctant to “get ahead” but cross-party consensus in Parliament meant that the UK “took a position to lead”.

“And the leadership did bring lots and lots of Europeans with us,” he said.

He added: “I definitely have a sense that that momentum has dropped back, and my experience of government is if you want to really drive things, you have to really do it every single day.

“You can’t just do a statement and then float around.”

Earlier this week, Prime Minister Sir Keir Starmer said that allies must “step up” support for Ukraine as he met President Volodymyr Zelensky.

Volodymyr Zelensky speaks to Sir Keir Starmer (Denes Erdos/AP)

He told Mr Zelensky the UK had an “unwavering” commitment to help the country defend itself against Russia’s invasion during bilateral talks at a European Political Community summit in Hungary.

Meeting Mr Zelensky one-to-one on the fringes of the event in Budapest, Sir Keir said: “As you know, our support for Ukraine is unwavering.

“And I strongly believe that not only should it be unwavering but we need to step up, and I was very pleased to be able to say that (today).

“It’s very important that we see this through. It’s very important that we stand with you.”

The Ukrainian leader replied: “We’re very thankful. We’re very proud that we have such bilateral relations between our nations.”