Boris Johnson ignored calls to retract his Jimmy Savile slur on Keir Starmer despite cops having to rescue the Labour leader from a mob of protestors falsely accusing him of "protecting" the paedophile.
Sir Keir was in Westminster with Shadow Foreign Secretary David Lammy when he was surrounded by anti-vaxxers shouting "traitor".
The Mirror understands some protestors had a noose and were repeating lies that Sir Keir failed to prosecute the serial paedophile when he was head of the Crown Prosecution Service.
In one clip of the incident, protestors could be heard swearing and bellowing "were you protecting Jimmy Savile" before police stepped in and walked Sir Keir to the safety of a cop car.
The incident comes just days after the Prime Minister falsely claimed in the Commons that Sir Keir failed to prosecute Savile - a fake claim regularly used by the far right.
But the Prime Minister failed to apologise or retract his remarks on Monday night, despite widespread calls for him to do so.
He tweeted: "The behaviour directed at the Leader of the Opposition tonight is absolutely disgraceful. All forms of harassment of our elected representatives are completely unacceptable. I thank the police for responding swiftly."
Head of the No10 policy unit Munira Mirza quit after the PM refused to apologise for the slur, saying "it was wrong" for him to imply the Labour leader was "personally responsible" for not prosecuting the paedophile.
Tory MP Julian Smith, Theresa May's former chief whip, led calls for the PM to apologise for the slur and withdraw his remarks about Starmer.
He tweeted: "What happened to Keir Starmer tonight outside parliament is appalling. It is really important for our democracy and for his security that the false Savile slurs made against him are withdrawn in full."
The Met Police said a man and a woman were arrested on suspicion of assault after a traffic cone was thrown at a police officer.
Labour MP Chris Bryant called the incident "appalling".
He said: "This is what happens when a Prime Minister descends into the gutter and recycles lies from hard-right conspiracy theorists. Political poison has an effect. Johnson has no moral compass."
Nicola Sturgeon has said the if the Prime Minister "has any decency at all" he would say sorry for "choosing to weaponise online conspiracy theories against opponents".
The First Minister of Scotland tweeted: "Any politician choosing to weaponise online conspiracy theories against opponents knows fine well that they risk stirring up the kind of hate and abuse that Keir Starmer experienced today.
"If he has any decency at all, the PM will now apologise unreservedly."
The Deputy Speaker of the Commons Dame Eleanor Laing, tweeted: "Tonight, the Leader of the Opposition, Sir @Keir_Starmer and the Shadow Foreign Secretary @DavidLammy were mobbed outside @UKParliament.
"This is unacceptable. Period. Elected representatives must be able to go about their work without the fear of verbal or physical attacks. It doesn’t matter which political party you support we all must stand up for freedom of speech and the rule of law."
Piers Corbyn, the brother of former Labour leader Jeremy Corbyn, was also among the crowd of anti-vaxxers, but was not thought to be involved in the fracas surrounding Sir Keir.
A spokesman for the Met Police said: "Shortly after 5.10pm on Monday, 7 February, a man who had been surrounded by a group of protesters near to New Scotland Yard, was taken away from the scene by a police car.
"A man and a woman were arrested at the scene for assault of an emergency worker after a traffic cone was thrown at a police officer.
"They have been taken into custody."
