The Irish Independent is reporting that Donaldson – later shot dead by the Real IRA at his Co Donegal hide-out – was outed by the British Government as a spy to send a message to the Provisionals that it had another, more valuable informant within its leadership ranks, the United States was told.
The astonishing claim from former Irish justice minister Michael McDowell came weeks after the former Sinn Fein official was shot dead by the Real IRA in a cottage near Glenties.
During a meeting with two senior US officials, Mr McDowell claimed Donaldson’s “outing” had been a “clear message” from the British Government.
His remarks are detailed in a confidential cable released by the whistle-blowing website WikiLeaks and published by the Irish Independent.
During a meeting with then US ambassador James Kenny and Special Envoy Mitchell Reiss in May 2005, Mr McDowell said he believed there was another, more important agent.
“McDowell believed that the outing of Denis Donaldson as an informant was a clear message from the British Government that it had another, more valuable, source of information within the republican leadership,” the cable reported.
In April 2006 he was found shot dead in Donegal – a few weeks after his location was made public.
In a separate meeting with Taoiseach Bertie Ahern, ambassador Kenny and Mr Reiss were told how Sinn Fein had seemed “surprised and shaken” by the Donaldson murder.
In February 2009 gardai announced they had a new lead in the inquiry and, later in the year, the Real IRA claimed responsibility for his killing.
Two months ago, two men were arrested for questioning over withholding information about the murder. The pair were held at Letterkenny garda station and questioned before being released without charge.