DUBLIN (Reuters) - Aer Lingus' (I:AERL) largest shareholder, rival Irish airline Ryanair, has yet to decide whether to back a deal to end a long-running pension dispute that is seen as key to the airline's valuation.
The pension scheme, which employees at Aer Lingus share with other aviation industry workers, has a deficit of more than 700 million euros (555 million pounds) compared to Aer Lingus' market capitalisation of 880 million euros.
The shareholder vote on the proposed one-off 191 million euro payment is the last major obstacle to a resolution. Aer Lingus' share price briefly climbed 10 percent when union members voted to back the deal earlier this month.
"We haven't made any decision yet. We will consider the EGM proposals and make a decision based on that," Ryanair Chief executive Michael O'Leary told Reuters.
Ryanair owns 30 percent of Aer Lingus, but is currently appealing an order by Britain's Competition and Markets Authority (CMA) for it to cut its stake to 5 percent.
O'Leary said he had not yet decided whether to ask for CMA permission to vote in the Dec. 10 extraordinary general meeting.
But he said he still opposed in principle the approach Aer Lingus management were taking, saying the deal was "just another roll over" by management to staff demands.
Analysts say the pensions issue has complicated attempts in recent years by Ryanair and 25 percent shareholder the Irish government to sell their stakes.
An Aer Lingus spokesman this month said no major shareholders had indicated how they would vote.
(Reporting by Conor Humphries, editing by David Evans)