Speaking earlier this week, the Irish pilots union, IALPA, said its members were considering following their counterparts in Italy and Portugal by backing industrial action. However, the airline negotiates pay and conditions on an individual basis at each of its bases and does not recognise unions.
"No more whipsawing. One pilot voice, one negotiating team now".
Ryanair is warning its pilots in Dublin that it will meet any attempts at industrial action "head on" and are not above having to remove some jets out of the capital.
In a memo to captains and first officers in Dublin, the Irish airline said it would freeze promotions, cut cash allowances and move pilots to different bases if they supported industrial action during ballots being held this week.
"The ANPAC representatives for pilots and flight assistants at Ryanair have asked the company to open negotiations so they can benefit from the branch agreement for Italian pilots", an ANPAC spokesman said.
"We may in due course be forced to look at re-basing some Dublin aircraft to lower-cost airports elsewhere, where our pilots continue to deal directly with us", he said.
"However, he stresses: ".we will NOT be dealing with Aer Lingus pilots or their union no matter how much or how long any such IALPA led action will occur".
Ialpa is part of trade union Impact.
Pilots and flight attendants plan to strike for four hours from 1 p.m. local time on December 15, the Anpac union said in a letter to the airline, adding that they're campaigning for the right to negotiate collective labor agreements, as well as on issues including social security, health care and vacation planning.
Ryanair, which does not recognise trade unions, said Anpac was an Alitalia union with "no role" in the company. The civil aviation union has notified the airline and the Italian government of the planned strike. The union says it has 280 members, representing around 40 percent of the Ryanair pilots based in Italy.
Ryanair has been left vulnerable after a staffing mix-up required it to squeeze six months of pilot leave into half that time.