It comes after the head of Aer Lingus' Central Representative Council, Myles Worth, said staff were broadly in favour of the takeover.
The Irish Congress of Trade Unions says it is surprised by the comments – and SIPTU's Owen Reidy says they do not represent all views.
“Some of the opinions he expressed – some of his colleagues would support some of the views he expressed, some of his colleagues wouldn't support” he said.
“I think people are making too much of what Myles said”.
“So I think until or unless tangible guarantees are given, the government have nothing to consider” he added.
