Sir Keir Starmer said more prisons will be built to manage overcrowding once the Government gets its “hands on the planning laws”.
Speaking to broadcasters in Berlin, the Prime Minister said the lack of prisons being built is one of the reasons for the current capacity crisis in jails across the UK.
It comes after Sir Keir said the decision to release prisoners early was a difficult one, and “goes against the grain of everything I’ve ever done”.
During the general election campaign, one of Labour’s key pledges was to unblock the planning system to allow developers to build on the “grey belt”.
On Wednesday, Sir Keir said: “We’ve got to change the planning regulation so we can build the prisons we need, because they’re taking far too long, it’s far too slow, and that’s amongst the reasons we’re in the position we are.
“And, as you’d expect from an ex-chief prosecutor, people do need to go to prison, and they need to know that the law is effective.”
Asked if he agrees with prisons minister James Timpson that the UK puts too many people in jail, Sir Keir replied: “I think (Mr Timpson) has got unparalleled experience in rehabilitation, and particularly those coming out of prison.
“I mean, he does employ a huge amount of people who come out of prison. His reason for doing that is to help them turn around their lives so they don’t go back straight into prison.
“I don’t think anybody would disagree with that, because the route back to prison involves another offence, which means another victim. If we can find a different approach for people, then all well and good.
“But, look, we need to build those prisons, and we will get our hands on the planning laws in order to do so.”
Earlier this week, the Prime Minister claimed the early release scheme is an essential part of the Government’s response to the recent riots and its ability to prosecute perpetrators of the violence.
In a speech in Downing Street’s rose garden, he said: “Not having enough prison places is about as fundamental a failure as you can get and those people throwing rocks, torching cars, making threats, they didn’t just know the system was broken, they were betting on it, gaming it.
“They thought ‘Ah, they’ll never arrest me, and if they do, I won’t be prosecuted, and if I am, I won’t get much of a sentence.’
“They saw the cracks in our society after 14 years of failure and they exploited them.”