The American government issued a statement saying it expected the government to pursue the matter, while a spokesperson for Interpol said gardai were obliged to honour an international warrant for the men’s arrest.

Bertie Ahern interrupted his summer holiday in Co Kerry to address growing international concern about the men’s re-emergence in Ireland last week. The three have been on the run since they were convicted of training terrorists in Colombia in June 2004.

The taoiseach said gardai would seek to talk to the men, particularly in relation to possible passport fraud. He added that any extradition request by the Colombian authorities would be dealt with by the courts.

Ahern branded their reappearance, just a week after the IRA issued a statement calling for the dumping of arms, as “unhelpful to the peace process”.

An Interpol officer said this weekend that gardai were obliged to arrest and question the men. She said the men were the subject of a “red notice” from the international policing organisation.

According to the officer, Niall Connolly, James Monaghan and Martin McCauley are all named in an Interpol file code-named The Amazon Project, updated on January 19.

“If these men are found in Ireland then they must be arrested,” she said. “They’re wanted to serve a sentence in Colombia, and Colombia has asked for their arrest and extradition if they are found.”

Charlie Bird, whose interview with one of them, James Monaghan, was broadcast on RTE on Friday night, refused to give gardai information about the fugitive’s whereabouts. He was driven by a contact to meet Monaghan on Friday.

The American government issued a response yesterday to news that the three fugitives had returned to Ireland last week.

The American statement said: “Three individuals tried and convicted in Colombia are fugitives from Colombian justice. We believe this is a matter that must and should be pursued by the Irish and Colombian governments. The US condemns contributions to terrorism, such as those of which the three men were found guilty, no matter where perpetrated.”

Ahern insisted that no deal had been done with Sinn Fein to give the men safe haven in the republic. He said the issue was never mentioned in talks with the republican leadership prior to the IRA statement of last month. The government had no knowledge of their return before the news broke on Friday, he said.

“I assume the offences they may or not be responsible for (in Colombia) are matters that the gardai could look at,” said the taoiseach.

“And, of course, any prosecutions in the normal way would be taken by the independent Director of Public Prosecutions office. If there is any issue, like passports for instance, that the gardai wish to raise with them, I understand they will do so.”

He said the men’s activities “whatever they were” had created a lot of difficulties for the Irish government, for Britain and for America. “These men have created in the peace process, on a number of occasions in the last few years, an enormous amount of difficulty and their return creates difficulty as well.”

Pat Doherty of Sinn Fein said he was glad to see them home and reunited with their families.

“There is a lot of nonsense in the media at the moment of a side deal having been done with the Irish government which is simply not true,” he said.

One republican, who has talked to Monaghan since his return, said: “Jim had been anxious to pay respects at the grave of his sister who died while he was in custody in Colombia.

“He does expect to be taken in and questioned by gardai at some stage.

“But he does not expect the Irish people to allow his return to Colombia for what would be a death sentence.”

A garda special branch source said the men’s appearance had taken them by surprise and said arrests were inevitable.

“They’ll probably be picked up under section 30 (of the Criminal Justice Act) and if there’s evidence against them of IRA membership, it’ll be thrown against them,” he said. “There’s no extradition treaty . . . but they’ll have to be picked up if there’s an international warrant.”

The three could also be arrested and charged for possession of forged passports.

Mary Harney, the tanaiste, who is acting as minister for justice while Michael McDowell is on holiday, was being briefed this weekend on developments by senior department officials liaising with gardai.

She said on Friday that there were “serious issues” to be raised about how the men returned to Ireland without valid travel documents.

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