UK Government sources have reacted with fury to a claim by Welsh Labour that Welsh Secretary Alun Cairns told an 'outright lie' to the Conservative party conference.
There is often friction between the Wales Office and the Welsh government over who gets the credit for good economic news, so Mr Cairns' speech was always likely to get a reaction.
It was the reference to Cardiff Airport's new service to Qatar that left Labour claiming that the Welsh Secretary had gone beyond exaggeration.
Welsh Government insiders had previously suggested that Alun Cairns was overstating his role in securing the new flights to Qatar, which he visited this weekend.
But, a source close to the Secretary of State responded with some annoyance to Labour's suggestion of an outright lie, describing it as "absolutely wrong".
It was pointed out that only a UK Government minister could instruct the British Ambassador to Qatar to support Cardiff's plans - or to arrange for the RAF Red Arrows to fly to the Gulf state to take part in Qatar Airways' 20th anniversary celebrations.