A ban on prosecutions of Northern Ireland veterans will be a key pledge in the Queen’s Speech, The Telegraph can disclose, as ministers prepare to introduce legislation within six months.

The law is expected to put an end to trials linked to the Troubles after a string of high-profile cases involving former soldiers collapsed due to a lack of admissible evidence.

There has been mounting concern among MPs and veterans that Boris Johnson would fail to deliver on his 2019 manifesto commitment to block further “unfair prosecutions”.

It is now expected the much-delayed Legacy Bill will be pledged in the Queen’s Speech next month as part of the Government’s legislative agenda for the coming year.

The bill would impose a statute of limitations on criminal prosecutions for offences committed during the Troubles up until the signing of the Good Friday Agreement in 1998.

Leo Docherty, the veterans minister, confirmed in an interview with The Telegraph that he expected the legislation to be introduced within the next six months.

Bill held up

He denied, however, that veterans had been forced to wait too long for the protections, after the bill was significantly held up by wrangling behind the scenes.

Speaking on a visit to the Invictus Games in The Hague, Mr Docherty told the Telegraph: “If this was easy, we would have done it already – and it is very complicated because it is Northern Ireland.

“But, I’m pleased to say, we expect from the Northern Ireland Office a bill that will give closure to veterans of (Operation) Banner, of whom there are some 300,000.  

“We expect this bill to give closure with honour and finality and I expect that to come forward very soon.”

Operation Banner was the name of Britain’s campaign in Northern Ireland between 1969 and 2007.

Mr Docherty is a close ally of the Prime Minister and acted as a member of his “Praetorian Guard”, which worked to quell the Conservative revolt against him over partygate earlier this year.

Setting out why the Legacy Bill had taken so long to be implemented, he claimed the process was “complicated” by the threat of legal action from Northern Ireland.

‘Trying to get it right’

“It’s really about ensuring that it was legally watertight – it has taken this long because we’re trying to get it right,” he said.

Sources with knowledge of the bill disputed this assessment and claimed delays instead stemmed from the fact ministers had originally conceived the protections as a “de facto amnesty”, which “no-one wanted”.

It is expected the law will now allow police and prosecutors to continue with criminal inquiries if individuals fail to participate in planned reconciliation hearings based on the model set up in post-apartheid South Africa.

News that the bill was finally due to be introduced received a cautious welcome from its supporters on Saturday, many of whom remain sceptical after a series of false starts by the Government.

Last year, there was a furious backlash after Conservative MPs were privately told the new law would be brought forward before the summer break, only for it to be shelved.

Johnny Mercer, the former veterans minister who was sacked before he could resign over the failure to introduce the legislation, told the Telegraph: “I’ll believe it when I see it, but a named bill in the Queen’s Speech is a significant move forward on this legislation that should have been enacted years ago.

“The delays have cost lives and put Northern Ireland veterans through hell needlessly.  My thoughts are with them today.”

Case of Dennis Hutchings

Philip Barden, a solicitor who represented Dennis Hutchings, the 80-year-old British veteran who died while on trial in Belfast last year, said: “This was an election promise and has been a long time coming.

“The personal cost of this political campaign being waged through the courts is enormous and very tragic. It should be brought to a swift end.”

The death of Mr Hutchings caused an outcry last October after Northern Irish prosecutors pushed ahead with a criminal case against him over a 1974 shooting, despite the soldier’s age and extremely poor health at the time.

Mr Docherty, himself an ex-Army officer, admitted the spectacle of elderly veterans being dragged through the courts had been “very painful” to watch.

A Government source said: “It is absolutely our intention to include this legislation to be introduced in the third session.

“Pressure on the parliamentary timetable meant it wasn’t introduced before the pre-election period in Northern Ireland.

“Our hope is for a swift introduction, as we are able to bring forward proposals having reflected on all our engagement following our command paper last summer, as we promised.”