Image copyright PA Media Image caption Boris Johnson (l) and Jeremy Hunt (r) made the comments during a head-to-head debate run by The Sun newspaper

Both candidates to be the UK's next PM have condemned tweets by Donald Trump which called on four Democratic congresswomen of colour to "go back".

During a head-to-head debate run by The Sun, Jeremy Hunt called the remarks "totally offensive", while Boris Johnson said they were "unacceptable".

But neither would go as far as branding the US president's comments racist.

Mr Trump said the women "originally came from countries whose governments are a complete and total catastrophe".

He faced a backlash for the series of tweets on Sunday aimed at Alexandria Ocasio-Cortez, Rashida Tlaib and Ayanna Pressley - who were all born in the US - and Ilhan Omar - who went to the US as a child refugee when she was 12.

His remarks were widely condemned as racist, and as having gone beyond previous statements and actions by the president that drew allegations of racism.

But Mr Trump doubled down on his comments on Monday, accusing the congresswomen of "hating our country".

Earlier, he also launched another Twitter tirade, calling on the women themselves to apologise.

All the women called the president racist and were backed by members of the Democratic Party.

Asked about the tweets during the debate, Mr Hunt - who is married to a Chinese woman - said he would be "utterly appalled" if someone said the same thing to their three children, who were born in the UK.

"It is totally un-British to do that, so I hope that would never happen," he added.

Mr Johnson said: "If you are the leader of a great, multi-racial, multi-cultural society, you simply cannot use that kind of language about sending people back to where they came from.

"That went out decades and decades ago and thank heavens for that."

He also echoed comments made by outgoing Prime Minister Theresa May, who earlier called the tweets "completely unacceptable".

Image copyright Getty Images Image caption Alexandria Ocasio-Cortez (left), Rashida Tlaib (centre) and Ayanna Pressley (right) accused the president of racism

But asked by The Sun's political editor, Tom Newton-Dunn, if they thought the comments were racist, neither candidate would say.

Mr Hunt said: "Look, I'm foreign secretary, this is a president of a country which happens to be our closest ally, and so it is not going to help the situation to use that kind of language about the president of the United States.

"I can understand how many people in this country would want politicians like me to use those words and would feel that sentiment, but...I hope I have made absolutely clear how totally offensive it is to me that people are still saying that kind of thing."

Mr Johnson said: "I simply can't understand how a leader of that country can come to say it."

Pressed again, he added: "You can take from what I said what I think about President Trump's words."

Media playback is unsupported on your device Media caption President Trump defends racially charged tweets

The candidates were also questioned about the possibility of a future trade deal with the US.

Mr Hunt said whenever he had met with the US president and his administration, they had "stressed how enthusiastic" they were to do a deal.

But he admitted that Mr Trump would be a "very tough and crude" negotiator.

Mr Johnson agreed, calling the administration "ruthless" and saying the country would put "tough conditions" on any agreement with the UK.

But he added that this did not mean it was "impossible to do a good deal".