A former director of public prosecutions (DPP) in Northern Ireland has accused the government of running "coach and horses" through the independence of the office.

Barra McGrory KC SC said a plan by the government to give the attorney general for England and Wales the final say in Troubles-related prosecutions in Northern Ireland was a "significant backward step".

He said had the proposed arrangement been in place when he was first appointed, he would not have applied for the job.

The Northern Ireland Office said the attorney general was also the advocate general for Northern Ireland, and the plan was a recommendation from Parliament's Joint Committee on Human Rights.

The plan is one of a number of changes proposed by the government to the Northern Ireland Troubles Bill, which is currently passing through Westminster.

Speaking to BBC News NI, McGrory warned the plan will be damaging for public confidence in the office he once held.

"If the director of public prosecutions can't be trusted to independently take decisions on troubles-related cases. Well, then, people are going to start questioning whether or not the DPP can be trusted to take decisions locally, and that is not healthy," McCrory said

McGrory was appointed DPP in 2011 and held the office for six years.

He took up the role after the criminal justice reforms in 2010 which ensured the office for the first time was completely independent. The reforms were a key part of the Good Friday Agreement.

But McGrory warned the government proposal would now "wipe away that independence in relation to Troubles-related cases".

"It has significantly undermined that very carefully crafted suite of reforms that were introduced back in the early 2000s. So it's a backward step," he added.

He also warned against a "two-tier" justice system with Troubles-related prosecutions being decided by the Attorney General of England and Wales with all other cases being considered by the local DPP.

"The public will say we are expected to have belief and trust in our DPP as someone who can take his decisions independently and impartially and on the evidence.

"But when it comes to this class of suspect, we're told that our DPP isn't good enough. So what does that say?"

He added: "We will have a hierarchy of victim, and that is not healthy."

McGrory also revealed that he would not have taken the job as DPP had the proposed new arrangement been in place when he was appointed.

"I was the first DPP to be appointed who was wholly independent and that was the reason why I applied for the job," said McGrory.

Asked how his former colleagues in the DPP might react to this proposed new arrangement, he said he didn't want to speak for the people he used to lead but he "can't imagine they are entirely happy about it".

He commended the staff of the DPP, which he described as "highly-skilled... independent people", and said they will address any Troubles-related cases that come to them from this legacy unit in that way.

"But the decision will no longer be made by their director; it will be made by an English attorney general, and I think that's not healthy for internal confidence."

McGrory also questioned the lack of response from the Irish government as a co-guarantor of the Good Friday Agreement, who supported the criminal justice reforms.

"I would have thought the Irish government would be deeply concerned about this reform. It is a reform that the Irish government would not tolerate in its own jurisdiction," he said.

He also questioned if the current Labour leadership appreciate the significant of this proposed change.

"I would have been shocked had Keir Starmer allowed this to happen as I know how much he valued the independence of prosecutorial decision making and he had a deep understanding of this jurisdiction," he said.

"I worry that the current occupant of Downing Street and the current secretary of state may not appreciate just how significant and potentially damaging this change is."

A Northern Ireland Office spokesperson said: "The Troubles Bill will repeal the Legacy Act's immunity scheme and enable families to seek answers and accountability about the deaths of their loved ones.

"To ensure confidence and consistency in any decisions to prosecute, the bill will introduce a requirement for the attorney general.

"In making such decisions, the attorney general must act quasi-judicially and independently of the government, applying well-established prosecution principles of evidential sufficiency and the public interest."