The Ministry of Justice is to cut its budget by 30%, according to documents leaked to the Observer newspaper.

The cuts are expected to be announced on Wednesday this week, when the government reveals the outcome of its spending review.

It is understood that the MoJ’s £9bn budget will be reduced to £6bn, and will include cuts to legal aid in divorce and family cases, immigration and medical negligence.

The leaked documents suggest that the cuts to legal aid could be more severe than the MoJ had originally planned. The MoJ is understood to be seeking to make savings of £291m from the £2.1bn legal aid budget by 2014, with £198m from civil and family cases and £93m from crime.

Justice secretary Kenneth Clarke was reportedly one of the last to settle his budget, and is believed to have lost out after more generous settlements were made on defence and education spending.

The leaked plans also suggest that the MoJ will be looking to reduce the prison population, and will press ahead with plans to close more than 157 courts across the country.

An MoJ spokesman said he could not comment on speculation about what might be contained in Wednesday’s spending review.