The Government is under huge pressure to sort out the problem of historic prosecutions having promised to do so in the run-up to the election and in its manifesto.

Further embarrassment will be heaped on the Government when Dennis Hutchings, a 78-year-old great-grandfather, is on trial, accused of the attempted murder of a man with learning difficulties who was shot and killed running away from an Army patrol in County Armagh in 1974.

Mr Hutchings, from Cawsand in Cornwall and who denies any wrongdoing, is undergoing kidney dialysis and the trial will have to be halted every two to three days so he can undergo life-saving treatment.

It is reckoned that up to 200 former soldiers are under criminal investigation for murder and other crimes alleged to have been committed during the Troubles.

Along with Mr Hutchings, five other soldiers have been charged including a former paratrooper accused of murder and attempted murder for his role in the Bloody Sunday killings in Londonderry in 1972.

Lawyers for Mr Hutchings have lodged a judicial review in the High Court claiming ex-soldiers are 54 times more likely to be prosecuted for historic offences than terror suspects on both sides of the sectarian divide.

Ministers have repeatedly tried to curb historic prosecutions of troops, promising some form of amnesty for events that pre-date the human rights act. But plans have been resisted by the Northern Ireland Office which is fearful that an end to troops’ prosecutions could risk peace in the province and the collapse of the Northern Ireland assembly, whose suspension was only restored in January.

Sinn Fein would strongly resist any amnesty while Unionists have also objected, fearing that any Republican terror suspects could go to court to claim amnesty for themselves.

Giving power of veto to the Attorney General could become enshrined in law within weeks - if the Downing St chooses that option.

Sources suggest it provides a simplified solution to a problem that has vexed Tory ministers for at least a year. But any change in the law will come too late for Mr Hutchings, whose trial will have already begun. It will also likely be subject to possible legal challenge because it threatens to undermine independent prosecutorial decision making.

The PPSNI has always insisted that decisions are taken purely on evidence put before them by police. They pointed out that in six years to 2017, it had taken “prosecutorial decisions” in 19 legacy cases, of which nine involved republican paramilitaries and four of paramilitary loyalists while three cases involved former soldiers and a further three involved ex-police officers.

“The PPS takes all of its decisions in accordance with the Code for Prosecutors,” said a spokesman.

A source said: “It seems very odd to take the decision making away from prosecutors in Northern Ireland because Westminster thinks the process has become too political to then give the decision to a politically appointed lawyer. I don’t know legislatively how that could work.”