Ditching controversial legislation dealing with Northern Ireland’s violent past risks at least a further five-year delay in tackling the thorny issue, a minister has warned.

Lord Caine was responding to calls at Westminster for the Government to rethink and even shelve the Northern Ireland Troubles (Legacy and Reconciliation) Bill, which has triggered widespread opposition at home and abroad.

But in the face of continuing criticism, the Tory frontbencher held out the prospect of making further changes to the proposed law in a bid to meet the concerns of victims and survivors.

The Bill would provide immunity for people accused of Troubles offences, as long as they co-operate with a new truth recovery body, and would also halt future civil cases and inquests linked to killings during the conflict.

Critics have denounced the draft legislation as offering an “amnesty” for killers and is opposed by all Stormont’s main parties and the Irish Government, as well as victims’ groups in Northern Ireland.

The UK Government has already proposed several amendments to the Bill, though the main elements of it remain.

Responding to criticism of the Bill in Parliament, Northern Ireland Office minister Lord Caine said: “I never anticipated that the amendments that I bring forward for this stage of the Bill would necessarily be the end of the story.

“I am looking at what more can be done… that will meet more of the concerns of victims and survivors.”

But he added: “If as some people are proposing we simply withdraw, delay or start again… then I think we really do risk spending at least another five years on this issue.”

Lord Caine went on: “The Bill does provide an opportunity to give more information to victims and survivors in a timely manner. It is the Government’s view that it should proceed.”

A leading voice pressing the Government to pause the Bill and start again was Northern Ireland’s first Police Ombudsman Baroness O’Loan.

The independent crossbencher, who during a previous debate recalled losing her unborn baby after surviving an IRA bomb in 1977, said: “The Government’s actions in bringing this Bill and continuing to push the Bill is doing very serious damage to our reputation as a country.

“It’s also doing huge damage, I think, and causing a lot of pain and grief and loss of trust in the United Kingdom Government among the people affected by the Bill.”

She added: “The people of Northern Ireland are united against this Bill. I would ask the Government again to pause and even to dispense with this Bill and to start again.

“There is no necessity and no urgency to dealing with this situation. There is a need to get it right.”

Lord Eames, the former archbishop of Armagh and Primate of All Ireland, said: “I have never, never come across such widespread opposition to a proposal such as this.

“There are so many people in Northern Ireland who are going to be denied justice.”

Urging ministers to “think again”, former deputy DUP leader Lord Dodds of Duncairn said: “It’s very, very clear that victims have been treated abominably by this Bill and this Government.”

He added: “I would appeal – listen to the victims.”

Former SDLP leader Baroness Ritchie of Downpatrick said: “They (the victims) feel this Bill robs them of their opportunity to access justice, to access investigations and to access inquests, which they believe, quite rightly, is their right.

“I agree there should be a pause placed on this Bill. That the Government should go away and think again.”

DUP peer and former education minister in Northern Ireland Lord Weir of Ballyholme said: “The Bill represents very clearly a denial of justice.”

Labour leader in the Lords Baroness Smith of Basildon said: “Our position remains the same. We do not support this Bill. We share the desire there should be a process. We share the desire to move forward and deal with the issues, but I have to say we do not believe this Bill is the case.”