Sir Keir Starmer has said he “understands what anchors” US President Donald Trump, having built a relationship on shared family values.

Despite “different political backgrounds” the prime minister said he found common ground with Trump, and that their “good personal relationship” helped land a vital US tariff deal.

Speaking on BBC Radio 4’s Political Thinking programme, Sir Keir revealed Trump reached out to console him after the death of his younger brother Nick Starmer on Boxing Day.

“For both of us, we really care about family and there’s a point of connection there,” he said.

“I think I do understand what anchors the president, what he really cares about.”

Sir Keir revealed he first spoke to Trump as prime minister after the then-presidential candidate was shot at a rally in July last year.

“That was a phone call really to ask him how it was, and in particular I wanted to know how it impacted on his family,” he said.

He added that Trump later called him after the death of his brother.

“We talked about my brother, and he was asking about him,” Sir Keir said.

Sir Keir denied this week’s painful series of U-turns on welfare reforms were because he had been too focused on foreign affairs and “taken his eye off the ball” domestically.

On Tuesday, the government avoided defeat on its proposals to overhaul disability benefits by offering late concessions to Labour MPs threatening to rebel.

The prime minister said he took responsibility for the episode, admitting it had been a “tough” few days but insisting the government would “come through this stronger” after a period of reflection.

The prime minister said forging close ties with figures such as Trump and French President Emmanuel Macron were “always in the national interest”.

“Building those relationships with international leaders is hugely important,” he said.

The prime minister said the personal rapport had helped secure a deal removing UK industries from some of the sweeping tariffs announced by Trump.

Before the deal he said he had seen “anxiety writ large” on the faces of British factory workers at Jaguar Land Rover in Solihull.

“After the deal, the relief was palpable,” he said.

Sir Keir said discussions “over a glass of wine” with Macron on a train to Kyiv had also paved the way for a new agreement with the EU, which he claimed would lead to lower food prices in British supermarkets.

“That is a good thing for millions of people across the country,” he said.

Sir Keir is due to meet Macron again next week as the French president comes to the UK for a state visit.

Tackling small boat crossings will be a key point of discussion, after Downing Street said last month the situation in the English Channel was “deteriorating”.

Official figures released this week showed nearly 20,000 people arrived in the UK in the first half of this year by crossing the Channel in small boats – up 48% on the same period last year.