The board of Aer Lingus could decide later today whether it will hold an emergency general meeting (EGM) of shareholders so they can vote on the Shannon-Heathrow controversy.
As a leading shareholder, Ryanair has called for the EGM to discuss the airline's plans to axe its Shannon to Heathrow service.
The Aer Lingus board is reportedly due to meet today to consider the request.
If the EGM is called, Ryanair has offered to team up with the Government to block the Shannon decision.
However, the Government has reportedly decided to back the decision if a vote is arranged.