The Minister for Transport Shane Ross has confirmed that a planned trip to North Korea is off.
On RTÉ's Prime Time programme, Mr Ross said that the idea had arisen several years ago while the Independent Alliance was in opposition, but that there was no firm proposal to go.
He said he, Mr Halligan and Finian McGrath had spoken regularly about making trips abroad and doing something constructive, but it was just an idea. "We never had a structured plan to do it," he added.
Asked if Minister John Halligan had written to the North Korean Embassy in London proposing a trip involving the three of them, Mr Ross said he didn't know, as he hadn't seen the letter.
North Korea's nuclear and missile programmes have led to increasing tension with US President Donald Trump, who has warned that the US may have to destroy North Korea if Kim Jong-un's regime threatens its neighbours.
North Korea has conducted six nuclear tests since 2006, with the largest in September drawing widespread international condemnation.
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