HORIZON scandal campaigner Alan Bates is demanding the government be held “responsible” for bankrolling hundreds of wrongful prosecutions of subpostmasters.

The lead campaigner blasted Lib Dem leader Sir Ed Davey for palming off concerns raised by victims of the Post Office’s Horizon IT system’s false accounting when he was postal minister in the Con-Dem coalition.

Mr Bates told the inquiry into the scandal today that ministers were “pumping huge amounts of money into Post Office year after year so they need to be held responsible.”

“They need to be addressed really about the way that they had been going on,” he added.

“It was very hard to engage them in it – not nowadays, they’re a bit more interested these days – but at that time, trying to get government to try and take it on board seriously, it was very hard.”

The Post Office has come under fire since the broadcast of ITV drama Mr Bates Vs The Post Office, which put the Horizon IT scandal under the spotlight.

More than 700 subpostmasters were prosecuted by the Post Office and handed criminal convictions between 1999 and 2015 as Fujitsu’s faulty Horizon system made it appear as though money was missing at their branches.

Mr Bates had his contract terminated by the Post Office in 2003 after refusing to accept liability for shortfalls in the accounts at his branch in Llandudno, north Wales.

Giving evidence today, he spoke of the organisation “attempting to discredit and silence me” over the course of his 23-year campaign.

He said he had “took offence” after then postal affairs minister Sir Ed refused to meet with him over his concerns.

Mr Bates had written to the minister on behalf of nearly 100 members of the Justice for Subpostmasters Alliance (JFSA) group  in May 2010.

Sir Ed replied saying the government had adopted “an arm’s length relationship with the company” so that the Post Office had “commercial freedom.”

Mr Bates criticised the “standard template response,” saying: “The government was the sole shareholder, they were the owners, as such, of all of this.

“How can you run or take responsibility for an organisation without having some interest in [it]… or trying to be in control?”

Rejecting this in his response, Mr Bates wrote: “It is because you have adopted an arm’s-length relationship that you have allowed a once great institution to be asset-stripped by little more than thugs in suits, and you have enabled them to carry on with impunity regardless of the human misery and suffering they inflict.”

Sir Ed and Mr Bates met that October after a Civil Service note recommending offering a meeting for “presentational reasons against the background of potential publicity.”

Mr Bates said nothing worth remembering came from the meeting.

Despite Sir Ed’s claims, the government was having “back channel communications” with the Post Office, the inquiry heard.

A July 2013 email, sent from shareholder executive Mike Whitehead from the Department for Business, Innovation and Skills to Post Office staff, showed the government requested a meeting with the Post Office to discuss how to respond to communications from Mr Bates – something he said he was unaware of at the time.

A spokesman for the Lib Dems claimed Sir Ed was “lied to” and was “sorry that he didn’t see through the Post Office’s lies, and that it took him five months to meet Mr Bates.”

The inquiry was shown slides from an undated presentation about Horizon integrity that claimed Mr Bates was sacked by the Post Office because it considered him “unmanageable.”

Former managing director of branch accounting Dave Smith’s presentation also claimed Mr Bates “clearly struggled with accounting” and that an internal review of his dismissal said: “The decision to terminate was not only right – it was the only sensible option.”

Asked if the Post Office had ever explained he had become “unmanageable,” Mr Bates smiled “no, not at all” and laughed at the suggestion of being “given copious support.”

He called the Post Office an “atrocious organisation” that is “beyond saving” and even said it should be sold to notorious gig economy union-buster Amazon.

Hundreds of subpostmasters are awaiting compensation despite the government announcing that those who have had convictions quashed are eligible for £600,000 payouts.