Far right fanatic Thomas Mair has been handed a whole life term for murdering the Labour MP in what prosecutors called an "act of terrorism".
Mrs Cox was stabbed 15 times and shot outside her constituency office in Birstall, West Yorkshire.
The trial of a man accused of murdering the MP Jo Cox in the days leading up the EU referendum by has been halted by action being carried out by prison officers.
Judge Mr Justice Wilkie said the officers' nationwide action means that defendant Thomas Mair, 53, cannot be brought to court from the prison where he is currently residing.
It meant the Old Bailey trial would have to be adjourned for the day, the judge told members of the jury.
The judge said: "The law is very clear that where, as here, a defendant does not attend his trial through no fault of his then in the absence of his consent...it is rarely ever appropriate for a trial to proceed in his absence."
Gardner Mr Mair denies Mrs Cox's murder, possession of a firearm with intent to commit an indictable offence and possession of an offensive weapon - a dagger.
His trial is set to resume at 10.30am tomorrow.
She may have only served her constituents for little more than a year, but those whose lives Jo Cox touched won't forget her lasting legacy.
Thomas Mair is being described as an extremist, a fanatic, an assassin – even ‘a constituent’. But make no mistake – he is a terrorist.
Thomas Mair "betrayed the quintessence of our country" in the senseless killing of MP Jo Cox, the judge said.