Dublin reaction: Opposition parties last night called on Taoiseach Bertie Ahern, and Minister for Justice Michael McDowell, who are both on holidays, to make a statement on the affair.
Fine Gael leader Enda Kenny said the Taoiseach had to clarify whether the issue was part of negotiations with Sinn Féin.
Labour's deputy leader Liz McManus said the return of the men one week after the IRA statement was "more than a coincidence", and urged the Government to make a categorical statement about whether there was any deal or discussion about them with Sinn Féin in recent months.
"The Colombia Three have never been honest or truthful with the Irish people about the activities in Colombia so anything they say about the circumstances of their return to Ireland should be treated with great caution," she said.
"We were told following their decision to jump bail that neither Sinn Féin nor any of their supporters knew anything about their whereabouts. Now a week after the IRA statement they suddenly reappear in Ireland - an event that most people will find difficult to accept as a mere coincidence.
"The appropriate legal authorities here will now have to consider the position, including the question of whether or not the possession by at least two of the men of forged Irish passports requires any further action."
A spokesman for the Taoiseach said the 'Colombia Three' were not discussed with Sinn Féin during discussions in the run-up to last week's statement by the IRA. "The Colombia Three were not part of discussions with Sinn Féin in any way, shape or form," he said.
He also said Mr Ahern and the Government had "no prior knowledge" of the return to the Republic of the three men.
The Government would, however, consider any request made by the Colombian authorities in relation to the three men, although it had no communication at this stage.
It is expected that Colombian authorities will make representations to the Government about their extradition back to Colombia in the coming weeks.
However, it is understood that because of the lack of an extradition treaty between Colombia and Ireland, the preliminary legal advice is that an extradition request is unlikely to succeed.
As the Government came under pressure from unionist politicians to have the men arrested, both the Government and the Department of Justice declined to comment on their legal status.
Asked whether the men could have breached Irish laws, and whether there would be any inquiry into how they returned into the Irish jurisdiction, the Government spokesman said it was a matter for the Garda and the Director of Public Prosecutions.