It was the highlight of the much-trumpeted Downing Street Declaration agreed by Enda Kenny and David Cameron in 2012. Wind energy would be harvested in Ireland and exported to Britain. The British would be helped to meet their EU green energy targets. Ireland would get a new export industry.

Pat Rabbitte has upped the odds in recent weeks by warning that the Anglo- Irish deal needed to clear the way is in trouble, because the British want to pay less in subsidies for onshore wind than the Irish supposed.

His British counterpart, energy secretary Ed Davey, is under the cosh from his treasury, which is concerned by the sums it is paying out in subsidies.

Brian Britten of Oriel Wind highlights that the project is a game of two halves: one offshore, the other on land. And offshore is in danger of being strangled because of the latter's problems.

Davey has stayed relatively silent, talking only, in a terse statement, of delays, not failure.

However, Rabbitte was vocal during his time in London this week leading the St Patrick’s celebrations.

The situation is not helped by the “state of chassis” now evident within the British system following Labour leader Ed Miliband’s pledge last year to freeze power prices for nearly two years, if elected.

Great politics it may be, but Miliband’s move was dreadful economics. Energy companies’ share prices have tumbled. More importantly, investment plans have been put in doubt.

Frightened, the Conservatives have played populist politics in return. Faced with such signals, civil servants, ever conscious of changing winds, tend to sit tight and do nothing.

Now, however, Kenny and Cameron have issued diktats, giving officials three months to see if a way through can be found. The statement left some wriggle-room for failure, it is fair to say.

However, an invitation from Government Buildings and No 10 is a politely worded instruction.

The ever-closer ties between Dublin and London may be about to earn their supper.