An NHS worker has apologised for screaming 'Nazi scum' at a Donald Trump supporter who was covered in milkshake at a protest earlier today.

Siobhan Prigent took to Twitter to say she was 'very sorry' for her behaviour at the demonstration in Parliament Square.

Video footage shows Miss Prigent and a number of marchers yelling at the semi-retired grandfather before he is hit with the drink.

He tells the angry mob that he is 'here to stay' before throwing the empty cup back at them as a female police officer tries to stop it turning into a brawl.

Ms Prigent, a clinical trials coordinator for University College Hospital, is seen holding a placard saying: 'This episode of Black Mirror isn't funny any more! #NoThanksNazis'.

The NHS worker, who is employed by the London hospital as a contractor through her company Vlek Ltd, now faces a battle to hold on to her job.

She apologised in a now-deleted tweet: 'I am very sorry for my behaviour today. I should have protested peacefully & I didn't, & I regret that.

Siobhan Prigent, pictured, has apologised for her behaviour at a London protest today in which marchers yelled 'Nazi scum' at a Donald Trump supporter

Ms Prigent, who works as a clinical trials coordinator at University College Hospital, is seen holding a placard saying: 'This episode of Black Mirror isn't funny any more! #NoThanksNazis'

Miss Prigent, from London, (pictured in the fracas) apologised in a now-deleted tweet: 'I am very sorry for my behaviour today. I should have protested peacefully & I didn't, & I regret that

'I've let myself down & I do understand that fully. There are two sides to every story, but my actions were my own, & that's on me. Please leave my family & friends out of it.'

Her apology comes after the Donald Trump supporter spoke out to reveal he was at the protest campaigning to protect democracy.

Speaking to MailOnline, the man, who refused to be identified, said he was peacefully debating with 'moderate lefties' and 'having a laugh with the majority of them' before the demonstration turned violent.

He said: 'We have to put forward how aggressive the left can be - it's not us, you know if they want to call me right wing because I'm supporting Trump then I must be right wing, but I'm not a racist.'

Speaking of the moment he was attacked, the man added: 'I came out to support Trump, to stop the left who since we voted for Brexit have been protesting against democracy.

'This is the democratically elected president of the free world. I just wanted a debate with the sensible left, I didn't expect any of what happened. I never wanted it to get violent, but I wasn't going to be intimidated.'

The grandfather said that the 'hardcore lot' became bitter 'because they couldn't answer the questions and the answers I was putting towards them'.

He explained that one of his friends had been hit by a milkshake first, and he was hit while helping him.

The man also claimed he was kicked in the legs, and attacked with a banner with a stick on the end. The demonstrators also attempted to remove his Make America Great Again hat - which he eventually got back.

The Londoner told how police officers removed him from the protest on Parliament Square for his own safety.

He told police that he didn't want to officially report what had happened as he knew 'nothing would come of it'.

The pro-Trump supporter caught the milkshake before throwing it back during the protest against the President today. He told MailOnline he was there supporting democracy

The pro-Trump supporter was escorted away by police for his own safety after demonstrators threw the beverage at him

'Some of them started calling us fascists, and we was telling 'em you're the fascists protesting against a democratically elected president of the free world,' he told MailOnline.

He continued: 'They have their democratic right to be there, and protest against him, and it was peacefully protesting.

'They was good to debate with and I was having a laugh with the majority of them then we started to get the hardcore lot coming in and start surrounding us.'

Earlier that day, the Trump supporter said the U.S. president made his 'grab them by the pussy comments' because he's 'still a kid at heart'.

Speaking to Joe.co.uk, he added: I see a link between Brexit and Donald Trump in globalism. Stopping globalism. I don't like the fact that there's globalism. I'm dead against that.

'I'm dead against unelected bureaucrats up in Brussels, who you cannot vote out. And they're forcing laws upon us that we don't even know about. I've no problem with Europe, it's the EU.'