Micheal Martin also said he would use the trip to focus on the role that Ireland has been playing in assisting the peace process in Colombia.

‘A far better course would be to admit that a mistake had been made and say that it would not happen again,’ a US diplomat said.

Diaz’s parents were snatched off the street just over a fortnight ago.

Diaz’s mother has been rescued but the Colombian authorities have stepped up the search for Luis Manuel Diaz.