Aer Lingus staff are being threatened with takeover by Ryanair if they fail to agree to massive cost-cutting.
Aer Lingus chief executive Christoph Mueller told the Financial Times Mueller that this would be "non-independence."
"If Aer Lingus isn't capable of mastering its own destiny, then of course the likelihood that some form of non-independence might occur is more likely," he said.
Ryanair has already made two attempts to take over Aer Lingus, it is expected they will make a third attempt in January.
Ryanair currently holds a 29.8 percent stake in Aer Lingus and had promised cheap trans Atlantic air travel for customers if the airline successfully takes over the company.
Ryanir says the "new" airline would carry over 50 million passengers a year. Mueller believes that it is now do-or-die for Aer Lingus and a deal with unions must be made.
"I believe there is a correlation between our ability to have an agreement with the unions and the likelihood of a bid," he said.