The Prime Minister has refused to say Donald Trump's claims that London wants to "go to Sharia Law" were "racist".
Sir Keir Starmer instead described the comments made by the US President following his recent state visit as "nonsense".
During a series of interviews following the embattled PM's keynote speech at this year's Labour Party conference, Sir Keir was repeatedly asked if Trump’s remarks about the capital, or accusing London Mayor Sadiq Khan, who is a Muslim, of driving London to Sharia law was racist.
Sir Keir told Sky News: “I'm not going to start down the road of discussing whether things said by others are racist or not... I have been really clear that the idea that in London we're introducing Sharia law is rubbish.”
He added: “[Sir Sadiq] is doing a very good job as mayor of London. And in fact, serious crime is down.
“And again, whether it's Andy Burnham or Sadiq Khan, we work very closely with our mayors. But I also have a very good relationship with Donald Trump, the President of the United States.
“We have a good personal relationship, and we work on behalf of our countries extremely closely together. And it's very important for the United Kingdom that I do so.”
Sir Keir also addressed comments he made about a Reform UK plan that could see migrants who live in the UK lawfully deported.
The PM said he did not believe Nigel Farage or Reform voters were racist, but suggested the policy was.
In his leader speech at Labour Conference Sir Keir pitted Labour directly against Reform UK as he warned his party was in a battle for the "soul" of Britain.
The Prime Minister used the address in Liverpool to take aim at Farage and the "politics of grievance".
He said the Clacton MP "doesn't like Britain" and wants to create “a competition of victims”.
“[Reform voters] are concerned about things like our borders,” he said.
“They're frustrated about the pace of change. So I'm not for a moment suggesting that they are racist.
“I was talking about a particular policy and making a distinction, and a really important distinction in my mind, between deporting those who have no right to be here, illegally here, which this government is doing and I agree with.
“And on the other hand, reaching into migrants lawfully here who've been here for years working in our hospitals, our schools, and deporting them, that to me would tear our country apart.”
The Labour leader, who described Farage as a "formidable politician", declined to say whether he believed his opponent was courting racists with the policy, but said minorities in the UK felt a "shiver down their throat".
Labour's conference will conclude on Wednesday with speeches from Environment Secretary Emma Reynolds and Energy Secretary Ed Miliband.
