The UK Government has challenged Ireland to set out its own record on tackling legacy issues, as it formally registered its regret at Dublin’s decision to take legal action against its Troubles legislation.

Northern Ireland Secretary Chris Heaton-Harris has written to Irish Minister for Foreign Affairs, Micheal Martin, questioning the move by Ireland’s Government to challenge the UK’s contentious legacy laws in the European Court of Human Rights.

The British Ambassador to Ireland Paul Johnston issued the letter on Sunday evening.

In it, Mr Heaton Harris again challenges Mr Martin to list the number of prosecutions mounted in the Irish state since 1998 related to Troubles incidents.

Aspects of the recently passed UK laws include a limited form of immunity from prosecution for Troubles-related offences for those who co-operate with the new Independent Commission for Reconciliation and Information Recovery (ICRIR).

The Northern Ireland Troubles (Legacy and Reconciliation) Act 2023 will also halt future civil cases and legacy inquests.

The UK Government’s laws are opposed by many victims groups in Northern Ireland and all the main Stormont parties.

Announcing the interstate case in December, Taoiseach Leo Varadkar said his administration was left with “no option” but to legally challenge the UK Government over the Legacy Act.

He said the “strong” legal advice was that the UK Legacy Act breached the UN Convention on Human Rights.

Tanaiste Mr Martin said they were taking the case reluctantly after having spent time trying to change the UK Government’s mind.

The Northern Ireland Office (NIO) confirmed to the PA news agency that a letter had been issued formally registering “profound regret” at the interstate case.

“The Secretary of State, in his letter, repeats his call for the Irish Government to clarify the number of criminal prosecutions brought in Ireland since 1998 relating to Troubles-related cases, and presses the Irish Government more widely to answer questions regarding its own record on tackling legacy issues in its own jurisdiction,” the NIO said in a statement.

The letter criticises the timing of the Irish decision, describing it as a “delicate time” in Northern Ireland amid the efforts to restore powersharing at Stormont.

The NIO added: “The decision also comes before the Independent Commission for Reconciliation and Information Recovery, led by Sir Declan Morgan as chief commissioner, is fully established and able to demonstrate its ability to discharge the UK’s international obligations.

“The UK Government reasserts its particular disappointment that the Irish Government has taken this course of action without, to date, any engagement with the ICRIR to understand better how it intends to implement the legislation and deliver for victims and survivors.”