Prisoners in England and Wales could be moved into portable buildings or released early as part of a huge extension of the electronic tagging scheme, as the justice secretary considers creative measures to solve the overcrowding crisis. Alex Chalk KC is expected to reveal a package of measures on Monday that could add 2,600 prison places across the estate, the Guardian understands. The lord chancellor has been under mounting pressure after revealing at the Conservative party conference that the government would seek to rent prison cells in foreign countries to help alleviate the burden. Last week the prison population rose to 88,016, an increase of more than 6,500 in a year and almost 10,000 up on two years ago. This week judges were told to delay the sentencing of convicted criminals currently on bail – including rapists and burglars – because prisons were full. Chalk could reveal next week that as many as 1,000 rapid deployment cells are to be installed in open prisons before the end of the year to boost spaces, and that officials will force more inmates to double up in cells. The home detention curfew tag programme was expanded earlier this year, allowing offenders to get off their sentences in prison six months early instead of four. Additional house blocks have been introduced at prisons, with the first 350 prefabricated “rapid deployment cells” installed already at five sites. With nonurgent maintenance work to be delayed so fewer spaces are out of use at one given time, and low risk-assessed prisoners being moved out of the closed estate into an open prison, officials estimate that as many as 2,600 spaces could be added before the end of the year. The government has built three new prisons and three are stuck in planning permission rows. On Tuesday the president of the Prison Governors Association blamed a lurch to the right by ministers for the overcrowding in jails, citing a stream of announcements about crimes that would now attract custodial sentences or longer sentences. The Ministry of Justice blamed the coronavirus pandemic and last year’s barristers’ strike for the backlog in courts, which it said was contributing to the high number of remand prisoners. A ministry spokesperson said: “We are categorical that the most serious offenders should be sent to prison and that anyone deemed a risk to public safety is remanded in custody while awaiting trial. Reports to the contrary are false. “This government has done more than ever before to protect the public and keep sex offenders locked up for longer, ending automatic halfway release for rapists and serious violent offenders and sending rapists to prison for three years longer than in 2010. “Following the pandemic and barristers’ strike, the criminal justice system has seen a significant spike in the prison population, with 6,000 more prisoners on remand than before the pandemic. While we are carrying out the biggest prison-building programme since the Victoria era, and have taken decisive action to expand capacity further by doubling up cells in the short-term, the prison estate remains under pressure. “The lord chancellor met criminal justice partners this week and will be setting out a programme of reform in the coming days to ensure that we can continue to strengthen public protection by locking up the most dangerous criminals.”