Sadiq Khan has reignited his long-running feud with Donald Trump - branding him an architect of a 'hostile environment'.

The London Mayor said he expected protests to erupt in the capital when the US president visits on July 13 to meet with Theresa May.

And he tore into the Prime Minister for extending a state visit to the President o quickly, and said he is relieved the looming trip will be a tone down affair.

Mr Khan and Mr Trump have locked horns repeatedly on Twitter over the past year - with both leaders taking angry swipes at the other.

Speaking on ITV's Peston on Sunday, Mr Khan also backed Londoners who want to join demonstrations against the visit.

Scroll down for video

Sadiq Khan (pictured on ITV's Peston on Sunday today) has reignited his long-running feud with Donald Trump - branding him an architect of a 'hostile environment'

The London Mayor said he expected protests to erupt in the capital when the US president (pictured yesterday) visits on July 13 to meet with Theresa May.

He said: 'I think there will be protests, I speak to Londoners every day of the week and I think they will use the rights they have to express their freedom of speech.

'But they must be peaceful, they must be lawful.

'As the Mayor of London it's probably inappropriate for me to join a protest when foreign leaders come into the UK. It's important though for me not to be scared to express my views about some of the things he's said.

'It's ironic that the architect of the hostile environment policy in this country has invited the architect of the hostile environment policy in the USA to London.'

The row between the pair began last June when the US President accused Mr Khan of having a 'pathetic' response to the London Bridge terror attack.

He tweeted: 'At least 7 dead and 48 wounded in terror attack,' the president wrote on his personal Twitter account, 'and Mayor of London says there is 'no reason to be alarmed!'

Theresa May (pictured going to church in her Maidenhead constituency today with her husband Philip) has faced criticism for extending a state visit invite to Donald Trump so soon after he took up office at the White House

But critics pointed out that the London Mayor was saying residents should not be alarmed at the increased police presence - not at the terrorists.

Since then the pair have repeatedly taken angry swipes at each other, with the London Mayor taking aim at the President when he retweeted the far right group Britain First.

Mr Khan said he is pleased the planned state visit, which would have seen the President hosted by the royals and given much pomp and ceremony, appears to have been kicked into the long grass.

And he called on Mr Trump to apologise for retweeting the fake video posted by Britain First.

He told the show: 'It's not about apologising to me - I think he should apologise for retweeting the tweets of a far-right group which has been set up intentionally to sow the seeds of division, Britain First.

'I've been quite clear I thought our Prime Minister was wrong in the speed with which she invited the President to a state visit to our country.

'So I welcome there's no state visit happening, the red carpet won't be rolled out.'