The Ministry of Justice, reportedly under orders to find a 5% budget cut, could come under pressure to channel more cash towards the prison estate after it was criticised by Whitehall’s spending watchdog for failing to provide safe and decent prisons.

Prime minister Boris Johnson has pledged to get tough on serious crime, recruiting 20,000 more police officers. However, the National Audit Office, in a report published today, said HM Prison and Probation Service faces prison population and capacity pressures because of increased demand for prison places.

In 2016, HMPPS committed to create 10,000 new for old prison places. So far, only 206 have been built with 3,360 under construction.

The report says: ‘Based on existing forecast operational capacity in September 2019 (excluding plans for 10,000 new places), it may need new prisons to be ready from late 2022. However, these forecasts are highly uncertain and do not include plans to increase sentence lengths for the most serious offences, which will likely lead to a faster and larger increase in demand, placing further pressure on available capacity.

‘In addition, actual demand will also be influenced by: future legislation; changes in crime; the speed at which police forces recruit and train new police officers; how police forces choose to prioritise their resources and deploy new officers; the speed at which the courts and Crown Prosecution Service process cases; and how defendants opt to plead and are sentenced.’

Government plans to increase the minimum sentence length for the most serious offences is likely to place further pressure on prison capacity, the NAO said.

Earlier this week Lord Falconer, a former lord chancellor who served under Tony Blair, expressed his concern about future spending on areas such as legal aid.

The Ministry of Justice, an unprotected department, has already suffered 40% budget cuts over the past decade.

Falconer said: ‘No one is interested in the justice sector. Everyone is interested in the health sector, the education sector, fighting terrorism. But no one is interested in the justice sector… We have got to make a common cause with the lord chancellor. We as politicians and practitioners have got to make common cause with him so he can fight in government for an increase in real terms for expenditure in these matters. If not, you will find things get considerably made worse.’