Prisons Minister Damian Hinds told MPs there had been an "acute and sudden increase in the prison population" in recent months and, as a result, the Operation Safeguard contingency plan had been launched for the first time since 2007.

He said the government had "long anticipated" the rise due to bringing in additional measures to tackle crime, and had been "planning ahead" for it.

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But Mr Hinds blamed strike action by the Criminal Bar Association, saying it had led to more people being held on remand.

And with court hearings now returning to normal, the government was "seeing a surge in offenders coming through the criminal justice system, placing capacity pressure on adult male prisons in particular".

Labour instead accused the government of cutting more than 10,000 prison places since it came to power in 2010, saying ministers were not "serious of protecting victims of crime".

'High demand'

Operation Safeguard is a protocol that sees the government write to the National Police Chiefs Council to request the temporary use of police cells.

When agreed, prisoners are then temporarily housed in cells in stations across the country, and the government works closely with the police on which ones to use.

Mr Hinds said it was an established procedure "to ensure our prison system can operate effectively and safely during periods of high demand".

It was last launched in January 2007, lasting until October 2008, and before that was instigated for four months in 2006.

The minister said further prison places would become available in the spring due to a new prison and additional house blocks being built.

A spokesperson for the Ministry of Justice added: "We are experiencing an unprecedented increase in the number of offenders coming into prisons in the north of England, partly as a result of the impact of the pandemic and the barrister strike action over the summer months.

"The public would rightly expect us to take the action necessary to create the extra spaces we need, and so we are working with the police to use a small number of cells in the short term so we can continue to put offenders behind bars."

But shadow justice secretary Steve Reed accused the government of leaving "murderers and rapists to roam our streets", claiming that had "cut the number of cells that they should be locked up in".

"Despite reports of rape and sexual offences hitting record highs, the Conservatives cut more than 10,000 prison places since 2010, while the Justice Secretary [Dominic Raab] is more interested in the fight to save his job than the fight against crime," he added.

"Our country needs a government that is serious about protecting victims of crime. Labour will get more police on the streets, a bigger say for victims, and a justice system that doesn't see criminals run loose."

There are currently 121 prisons in England and Wales and 82,700 people in jail.