Britain must be prepared to fight future wars without US after Trump destroys 'assumptions', defence secretary says

Ben Wallace says US president’s decisions in Iran and Syria means UK ‘needs to diversify our assets’

Britain must be prepared to fight future wars without the US, the defence secretary has warned after admitting the UK is currently “dependent” on the American military.

Ben Wallace said Donald Trump’s unpredictable moves in the Middle East, including his withdrawal from Syria and the assassination of Iranian general Qassem Soleimani, had disrupted historic precedents.

“The assumptions of 2010 that we were always going to be part of a US coalition is really just not where we are going to be,” he told the Sunday Times.

“We are very dependent on American air cover and American intelligence, surveillance and reconnaissance assets. We need to diversify our assets … we are going to have to make decisions that allow us to stand with a range of allies.”

Mr Wallace said he was kept awake at night be the prospect of the US withdrawing from global leadership.

His warning came as Boris Johnson prepares to lead what is being billed as the “deepest review” of Britain’s security, defence and foreign policy since the Cold War.

The prime minister has been criticised for his absence during key moments of escalation between the US and Iran over recent weeks.

Brandon Lewis, the security minister, said Boris Johnson was working with the international community to “de-escalate that whole situation”.

Asked if Mr Trump had acted responsibly by ordering Soleimani’s death, he said it was “it’s absolutely right for the US to be able to defend itself”.

“The US took a decision about the right way to do that and we have to respect that,” Mr Lewis told Sky’s Sophy Ridge on Sunday programme.

“The prime minister’s focus with partners and talking to president [Hassan] Rouhani has been around de-escalating the situation. That is what’s in the global best interest for all of us.”

Mr Lewis echoed the defence secretary’s comments by saying that Britain would work “globally” with partners, adding: “The US plays an important part in that but we also work with partners across Europe and other places around the world.”

He said the UK’s relationship with the US went beyond individual leaders and would continue through channels including Nato.

Mr Lewis said the government was working to ensure a transparent investigation into the downing of a passenger plane that was mistakenly targeted by Iranian forces in Tehran.

Four British victims were among the 176 people killed on board Ukraine International Airlines flight PS752, which was shot down on Wednesday shortly after take-off on 8 January.

President Rouhani called the missile strike a “disastrous mistake”, after military chiefs had for days denied responsibility.

Tensions with the UK rose further on Saturday after the British ambassador to Iran was detained in Tehran.

Rob Macaire said he was arrested after attending an event that had been advertised as a vigil for victims of the plane crash.

“Normal to want to pay respects – some of victims were British,” he wrote on Twitter.

“I left after five minutes, when some started chanting. Detained half an hour after leaving the area. Arresting diplomats is of course illegal, in all countries.”

Dominic Raab, the foreign secretary, called the arrest a “flagrant violation of international law” and said there were no grounds or explanations by Iranian authorities.

He added: “The Iranian government is at a crossroads moment. It can continue its march towards pariah status with all the political and economic isolation that entails, or take steps to de-escalate tensions and engage in a diplomatic path forwards.”