The suspension of the Northern Ireland Assembly in 2002 might have been avoided if the paramilitary watchdog, the Independent Monitoring Commission (IMC), had been set up sooner, former First Minister Lord Trimble has said.
The watchdog was created by the UK and Irish governments in January 2004 to monitor paramilitary activity and the normalisation of security measures in Northern Ireland.
In 2010 a decision was taken to bring the commission's work to an end, and the group presented its final report to the two governments in March last year.
As peers debated the report on 18 January 2012, Lord Trimble said: "I've always felt that if we'd had this body in existence before then, we might very well have avoided that collapse and the consequent nearly five-year hiatus in the institutions in Northern Ireland."
"But," he added, "it came, and it did have a very positive effect".
The former first minister claimed he encountered "fierce opposition" from the Northern Ireland Office at Westminster when he and his colleagues first suggested creating such a body.
Opening the debate, Liberal Democrat peer Baroness Harris of Richmond praised the "fantastic" work of the IMC.
She said Northern Ireland had come a long way in recent years but paramilitary violence still posed a threat, adding: "We must be vigilant about any future occurrence."
Baroness Harris hoped further integration would enable young people to "live together" and "respect" each other's cultures.
For the government, Lord Shutt of Greetland said the paramilitary watchdog had played a "crucial part in supporting and enabling historic changes" in Northern Ireland over recent years.
"It has assisted Northern Ireland's transition to a peaceful, stable and inclusive society," he added.
He promised that the UK government would do all it could to work with the Northern Ireland Executive on the issue of a shared future.