Former Post Office chairman Henry Staunton will face questions from MPs on Tuesday amid a row with Business Secretary Kemi Badenoch over delays to subpostmaster payouts.
The Business and Trade Committee said that the current Post Office chief executive, Nick Read, and subpostmasters including Alan Bates will also answer questions during the hearing.
The parliamentary select committee said the witnesses will update MPs on progress on redress to victims of the Post Office Horizon scandal.
The Horizon IT scandal saw more than 700 subpostmasters handed criminal convictions between 1999 and 2015 as Fujitsu’s faulty Horizon system made it appear as though money was missing at their branches.
Hundreds of subpostmasters are still awaiting compensation despite the Government announcing that those who have had convictions quashed are eligible for £600,000 payouts.
Mr Staunton, who will answer questions on Tuesday afternoon, stepped down from the Post Office amid ongoing tensions last month.
The former WH Smith executive has since been involved in a deepening row with Ms Badenoch after he claimed he had been told to delay payouts to the subpostmasters affected.
Ms Badenoch tolds MPs he had spread “made-up anecdotes” following his dismissal.
However, ministers are under pressure over allegations a senior civil servant told Mr Staunton not to focus on “long-term issues” and to protect his organisation’s finances.
Mr Staunton is said to have been told during a meeting with Sarah Munby, who was then permanent secretary at the Department for Business, Energy and Industrial Strategy (BEIS), to “hobble” into the next general election, according to notes reported by The Times newspaper.
Ms Badenoch then referred to the dispute last Thursday, tweeting: “It’s important that people have trust in all we’re doing to get them justice.
“It’s frustrating dealing with false allegations that break that trust, but we won’t be distracted.
“The law is expected to come into effect by the end of July and apply to convictions in England & Wales.”
On Tuesday, MPs will also hear from legal representatives from the Department of Business and Trade administering the group litigation order (GLO) scheme designed to compensate 555 subpostmasters, and lawyers for claimants of this and all other schemes, the Commons said.
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