The Minister for Justice has ordered an independent inquiry into allegations that the Garda Síochána withheld information from their counterparts in Northern Ireland which it is alleged could have helped to prevent the Omagh bombing.
Mr O'Donoghue has established a three-person team to examine the claims, which were made by a suspended Garda officer to the North's Police Ombudsman, Ms Nuala O'Loan.
Ms O'Loan met the Minister for Foreign Affairs, Mr Cowen, last March to discuss the claims that vital information on the bombing was withheld.
The Ombudsman's executive director, Mr David Wood, a commander with the London Metropolitan Police, also attended the meeting.
It has been claimed that several days before the Omagh bombing, an informant to the Garda Special Branch told his handler - an officer based in Dublin - that republican dissidents who had previously asked him to steal a car said they no longer needed a vehicle because they had already obtained one.
The information was allegedly not relayed to the RUC even though the informer had stolen cars previously used in dissident republican operations.
In a statement last night, the Minister said he decided to order the inquiry "notwithstanding the source of the allegations and the circumstances surrounding the manner in which very sensitive information impinging on issues of national security was made available".
The decision was taken after consultations with the Garda Commissioner, Mr Pat Byrne, who, the Minister said, had assured him "there is no basis for any suggestion" that the allegations were true.
The three members of the inquiry team are Mr Dermot Nally, former secretary to the Government; Mr Eamon Barnes, former Director of Public Prosecutions; and Mr Joe Brosnan, former secretary of the Department of Justice.
They have already held their first meeting, and the Minister said he would make a further statement as soon as their findings were made available to him.
The Garda sergeant at the centre of the allegations is currently suspended from duty facing charges as part of a major inquiry into corruption claims in Co Donegal.
Representatives of the Omagh families are to meet the British Home Secretary, Mr David Blunkett, in London today.