Labour’s Emily Thornberry has branded Donald Trump a “racist” and compared his presidency to “an asteroid of awfulness” that has befallen the world.

The shadow foreign secretary said it was wrong for Theresa May to offer the US president a state visit and said Londoners and the rest of Britain were repelled by his views.

It comes after Mr Trump confirmed he would not open the new US embassy next month, blaming the Obama administration’s decision to move it to an “off location” in a “bad deal”.

Ms Thornberry said it was clear that Mr Trump “doesn’t have a real grasp” on how trade deals work, when he said it would be easy to do a deal with the UK within weeks.

The Labour frontbencher was also scathing about the US president following reports he had branded Haiti and some African states “shithole” countries.

She told the BBC’s Andrew Marr Show: “He is an asteroid of awfulness that has fallen on this world. I think that he is a danger and I think that he is a racist.”

After Mr Trump cancelled a visit to open the new US embassy next month, Ms Thornberry said: “What kind of visit did he think he was going to get? Did he think he was going to visit in a gold coach?

“Well, you know, Londoners are not terribly impressed with him. Surprise, surprise, and neither, frankly, are the British.”

The Labour frontbencher added: “I don’t want him to come to the country. I don’t think that he should have been given an invitation in the way that he was. That it was wrong for Theresa May to so prematurely offer him a state visit.

“I think that it embarrasses the Queen. I think that it is a humiliation for her. I think it is wrong to have brought her into this in this way.”

Any visit from Mr Trump would bring about “major demonstrations” and the Government should advise Washington over the security considerations, she said.

Ms Thornberry said: “He did at one stage say he didn’t want to come to Britain until the British had learned to love him and I was quite relaxed about that.”

Pressed on whether the “special relationship” had been damaged by the growing row, Ms Thornberry said a trade deal after Brexit could still happen without him.

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She said: “He said that he wanted to do a trade deal with Britain and he thought that he could do that in weeks. That shows that he doesn’t have a real grasp of what a trade agreement actually is. These things take years.

“Secondly it won’t be for him to be making a trade deal. There are many people in the United States – we are not in a medieval court.”

Downing Street maintains that Mr Trump has been offered a state visit and it cannot be taken back, except by the Queen.

Brandon Lewis, the newly appointed Tory chairman, said it was right for the US president to have a welcome in Britain.