The Competition & Markets Authority has reiterated its demand for Ryanair to sell most of its holding in Aer Lingus.
The low-cost carrier must cut its stake in the Irish flag-carrier from 29.8 per cent to five per cent.
Ireland’s government has agreed to sell its 25 per cent stake in the airline to International Airlines Group – owner of British Airways and Iberia.
Ryanair reacted angrily to the latest decision.
A statement read: “Today’s Competition & Markets Authority decision rejecting Ryanair’s request to review its order to divest Ryanair’s 29.8 per cent minority stake in Aer Lingus is manifestly wrong and flies in the face of the current IAG offer for Aer Lingus.
“When the only basis for the CMA’s original divestment ruling was that Ryanair’s minority shareholding was or would prevent other airlines making an offer for Aer Lingus, the recent offers by IAG for Aer Lingus totally disprove and undermine the bogus theories and invented evidence on which the CMA based its untenable divestment ruling.”
Ryanair chief executive Michael O’Leary has fought previous attempts to force Ryanair to divest its stake in Aer Lingus.
The low-cost carrier has also twice attempted to takeover the Irish rival.
O’Leary has said his company would consider any offer from IAG for its shares in Aer Lingus.
However, it is thought the low-cost carrier will expect concessions from IAG, including a number of its slots at Heathrow airport.
Ryanair has instructed its lawyers to appeal today’s decision to the Competition Appeal Tribunal, given that it is factually unsustainable and legally flawed as the IAG offer for Aer Lingus proceeds.