Post Office campaigner Sir Alan Bates has threatened legal action if financial redress for victims doesn't come soon.
Sir Alan, speaking after accepting a knighthood for services to justice, told Sky News: "If we need to fundraise for a court case, we will."
In a letter sent to hundreds of former sub postmasters last week, he called for a March 2025 deadline for financial redress for those caught up in the Post Office scandal.
"They (financial redress schemes) can't be allowed to drag on for years again," he said. "There's no reason it's just the bureaucracy driving them into the ground again."
Hundreds of sub-postmasters were wrongly accused of stealing after faulty Horizon computer software threw up false shortfalls in branches between 1999 and 2015.
Sir Alan said that he had not "heard a word" from the new government on the compensation schemes.
"There are potential legal avenues we can take but it's going to then be another year, 18 months, for the group," he added.
"If we can't get these things resolved shortly, if we can't get an affirmation from them of a March 2025 deadline, then we may as well follow other routes.
"And I know we've got the support of the nation behind us, if we need to fundraise for a court case we will."
Sir Alan spoke to Sky News after being knighted at Windsor Castle by the Princess Royal for services to justice.
He said he and his wife, now Lady Bates, were accepting the honour "on behalf of the whole group and the suffering everyone's gone through".
He insisted that if the knighthood helps "take our battle forward" - then it is "a real honour from that point of view."
While Lady Bates described her husband's knighthood as "a reaffirmation of how amazing the journey has been for Alan and for myself".
Former Post Office boss Paula Vennells was stripped of her CBE earlier this year after TV drama Mr Bates v The Post Office drew widespread attention to the scandal.
Seven months on and Sir Alan said that his knighthood was for all the Post Office victims.
"We deserve it, unlike she (Paula Vennells) did - she drove the business into the ground into such disrepute," he added.
When asked about the news that Post Office chief executive Nick Read will be stepping down from the role next year, Sir Alan said he was not confident in the organisation's management.
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"It needs major capital investment," he said, "There's a wonderful, wonderful network of hard-working individuals running these post offices around the country but it needs fresh direction."
He added: "I've said before it should be sold off for a pound to someone like Amazon, not actually Amazon, to someone who can take it on board."
Sky News has approached the government and Post Office for a statement in response to Sir Alan's comments.
(c) Sky News 2024: Post Office campaigner Sir Alan Bates threatens legal action over compensation delays
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