The Irish ambassador to Iran is to meet the Iranian foreign ministry in Tehran later today to discuss the case of an Irish-born man who is being detained there.
David Bloomer is one of five sailors detained in Iran last week after their boat strayed into Iranian waters.
The Irish Department of Foreign Affairs is liaising with the foreign office in London and has spoken to the Iranian embassy in relation to the case.
The Department has also been in contact with members of his family in Ireland and the Middle East.
Mr Bloomer was travelling on a British passport and the Foreign Office in London is involved in contacts with officials in Iran.
The Department of Foreign Affairs says it has received no requests for assistance in relation to the case.
According to the Press Association Mr Bloomer is believed to hold dual British and Irish nationality and is said to be in his 60s.
The four other sailors detained are British and have been named as Oliver Smith, Oliver Young, Sam Usher and Luke Porter.
Chief of staff to President Mahmoud Ahmadinejad, Esfandiar Rahim Mashaie, confirmed the detention of the sailors this morning.
He said the next move would be decided by the judiciary.
'If these people's ill-intention is proven, they will be dealt with seriously and firmly,' he said, adding Tehran had in the past dealt firmly with people who entered Iran illegally.
Britain has said it has 'no argument' with Tehran, stressing that the seizure was purely a consular matter.
Seeking to head off a diplomatic row, British Foreign Secretary David Miliband stressed that the group had been treated well.
'There is certainly no confrontation or argument,' he told BBC radio, a day after London went public about the seizure.
'This is a purely consular matter, and we look forward to it being treated as such.'
The five were sailing from Bahrain to the start of a race in Dubai when their yacht, 'The Kingdom of Bahrain,' was stopped on 25 November in the Gulf.
The yacht may have been drifted into Iranian waters after breaking its propeller en route to the Dubai-Muscat Offshore Sailing Race, which started last Thursday, British media reports said.
