There would be no chance of a US-UK trade deal if there was any weakening of the Good Friday Agreement, US Speaker Nancy Pelosi warned last night.

The US House of Representatives speaker told a packed lecture theatre that the Good Friday Agreement was a model that could not be 'bargained away in another agreement'.

Speaking at the London School of Economics on Monday Ms Pelosi said passing a trade bill in Congress would be very hard and was 'no given'.

Earlier in her trip, Ms Pelosi reprimanded Labour leader Jeremy Corbyn for his failure to tackle anti-Semitism.

There would be no chance of a US-UK trade deal if there was any weakening of the Good Friday Agreement, US Speaker Nancy Pelosi warned last night (pictured)

The US House of Representatives speaker told a packed lecture theatre that the Good Friday Agreement was a model that could not be 'bargained away in another agreement' amid stalemate

She added: 'First of all it is very hard to pass a trade bill in the Congress of the United States, so it's no given anyway.

'But if there were any weakening of the Good Friday accords there would be no chance whatsoever, a non-starter for a US-UK trade agreement.

'The Good Friday accords ended 700 years of conflict.

'This is not a treaty only, it's an ideal, it's a value, it's something that's a model to the world, something that we all take pride in.

'It was a model and other people have used it as a model and we don't want that model to be something that can be bargained away in another agreement.'

Ms Pelosi said she had met Labour leader Jeremy Corbyn and senior Tories, and spoken to Prime Minister Theresa May on the phone.

She added: 'We have met the speaker. We met with the leader of the opposition Jeremy Corbyn and we met with those who left the Labour Party and we made it clear to all that if there's any harm to the Good Friday accords - no trade treaty.

'Today we met with the Government, with the Chancellor of the Exchequer and deputy prime minister and those who are in opposition in the Conservative Party and to all of them we made it clear: don't even think about it.

'Every single person, including Theresa May, who I spoke to over the phone, said 'don't worry about that, we would not even go there'.

'That's a place we cannot go.'

Earlier in her trip, Ms Pelosi reprimanded Labour leader Jeremy Corbyn (pictured yesterday in Halifax) for his failure to tackle anti-Semitism

After the first round of her meetings, including with three ex-Labour MPs who quit over the failure to tackle anti-Semitism, Ms Pelosi declared 'the importance of standing unequivocally against anti-Semitism wherever it is found'.

Mrs Pelosi – who was instrumental in getting Barack Obama's health care law through the House in 2010 – was in London yesterday to meet with Chris Leslie and Mike Gapes, who defected to form The Independent Group, and Ian Austin, who now sits as an independent.

She tweeted that they had had an 'important discussion... to hear their perspective on Brexit [and] why they left the Labour Party'. Mrs Pelosi was also due to meet Mr Corbyn last night.

Nancy Pelosi said she was pleased to have had a 'candid discussion' with Jeremy Corbyn

Her remarks came as Lord Falconer warned that the Labour Party's failure to tackle anti-Semitism was a 'very real threat' to its survival.

The former lord chancellor, who has been asked by the party leadership to hold an investigation into anti-Semitism, also said Labour could not be seen as an alternative government unless it is 'absolutely vigorous and effective' in removing people who are anti-Semitic.

He said: 'There is too much a sense that anti-Semitism is not being properly dealt with. I think this is a very, very real threat to the party.

'How can you convince people that you are a serious, moral, decent party if you are anti-Semitic? How can you claim to be an alternative government if you are anti-Semitic? We have to do something about it.'

The comments came after The Sunday Times published details of a secretly recorded meeting between Mr Corbyn and Labour MP Dame Margaret Hodge in February when he outlined his intention to appoint Lord Falconer to review the party's complaints process.

The newspaper quoted Mr Corbyn saying: 'The point of him [Falconer] is that he will look at the speed of dealing with cases, the administration of them, and the collation of the evidence before it is put before appropriate panels and things.

Mrs Pelosi – who was instrumental in getting Barack Obama's health care law through the House in 2010 – was in London yesterday to meet with Chris Leslie and Mike Gapes, who defected to form The Independent Group, and Ian Austin, who now sits as an independent

'Because I was concerned that evidence was either being mislaid, ignored or not used and that there had to be some better system.'

A Labour spokesman said the party takes allegations of anti-Semitism seriously, adding: 'This shows Jeremy Corbyn's desire to make procedures as robust and efficient as possible and to rebuild trust with the Jewish community.

'We are committed to challenging and campaigning against it in all its forms. All complaints... are fully investigated in line with our rules and procedures and any appropriate disciplinary action is taken.'

Dame Margaret told the BBC: 'The reason, actually, that I recorded that particular tape was as an insurance policy. I was having a one-to-one meeting with Jeremy Corbyn and, ironically, I didn't want what I said to be misrepresented.'

Labour MP Ronnie Campbell said taping Mr Corbyn was unacceptable. He said: 'I think it's deplorable that somebody goes to a private meeting with the leader and records the conversation.'