In the first Prime Minister's Questions of the year, Rishi Sunak said he plans to make sure those convicted as part of the Post Office scandal get exonerated through an act of parliament.

As well as announcing new legislation, which the postal affairs minister said would take "some weeks to deliver", the prime minister said upfront compensation of £75,000 will be awarded to the 555 postmasters who took their case to the High Court in 2019 as a group litigation.

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The government has come under increased pressure to take action on the Horizon scandal following the airing of ITV drama Mr Bates Vs The Post Office last week.

More than 700 sub-postmasters and sub-postmistresses were prosecuted for accounting errors relying on data from the faulty Horizon software.

Once they are exonerated, the government has confirmed victims will be eligible for at least £600,000 compensation, depending on their circumstances.

The scheme applies to England and Wales.

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'The victims must get justice'

Speaking in the House of Commons, Mr Sunak said: "Mr Speaker, this is one of the greatest miscarriages of justice in our nation's history.

"People who worked hard to serve their communities had their lives and their reputations destroyed through absolutely no fault of their own.

"The victims must get justice and compensation. Sir Wyn Williams' inquiry is undertaking crucial work to undo, to expose what went wrong, and we've paid almost £150m in compensation to over to 2,500 victims."

Mr Sunak said the new legislation would ensure victims are "swiftly exonerated and compensated".

The prime minister's spokesman said the intention was to have the legislation introduced within weeks and compensation paid out by the end of the year.

How will new legislation work?

Kevin Hollinrake, the postal minister, provided an update on the government's plan to the Commons after PMQs.

He said all those claiming compensation will sign a statement of truth to say they did not commit the crimes of which they were accused.

"Anyone subsequently found to have signed such a statement untruthfully will be putting themselves at risk of prosecution or fraud," Mr Hollinrake said.

The minister admitted this was not "foolproof", but it was a "proportionate" device "which respects the ordeal with which these people have already suffered".

He also said the government was considering whether people who had their appeals refused already would have their convictions overturned.

Numerous ways to fast-track the overturning of convictions had been mooted prior to today's announcement.

Some had called for a mass appeal before the Court of Appeal, while others wanted legislation to overturn the convictions or even a pardon from the King.

It is not clear exactly how the mechanics of the Commons overturning hundreds of prosecutions will work.

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Labour welcomes PM's plan

Sir Keir Starmer, the Labour leader, indicated earlier this week that his party would support an attempt through law to overturn the convictions.

Responding to Mr Sunak today, Sir Keir said the scandal "is a huge injustice"

"People lost their lives, their liberty, and their livelihood, and they've been waiting far too long for the truth, for justice, and for compensation," he added.

"So I'm glad the prime minister is putting forward a proposal.

"We will look at the details, and I think it's the job of all of us to make sure that it delivers the justice that is so needed."

James Strong, the director of Mr Bates vs The Post Office, told Sky News that the reaction to the programme has been "unbelievable" and "astonishing".

He told presenter Mark Austin: "For it to transcend into the national consciousness in quite the way it's done, quite the scale it's done, it's taken everybody by surprise who made it. So we're thrilled and delighted, but slightly shocked as well."

He added: "We strove and we put everything into it to make it... as compulsive and as watchable as possible."

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Last year, the government announced that every wrongly convicted sub-postmaster and sub-postmistress would be offered £600,000 in compensation.

In 2019, the Post Office agreed to pay £58m to 555 sub-postmaster and sub-mistresses.