The Oireachtas Transport Committee heard from a representative of Virgin Atlantic, who discussed the airline's concerns over the IAG bid for Aer Lingus.
Joe Thompson, director of network and alliances at the airline, said Virgin is unashamedly competitive and wanted to ensure that the customer will be protected from any acquisition by IAG, which he said cannot go unchecked.
In his opening statement Mr Thompson questioned if legal guarantees had been sought from IAG to maintain seat capacity by Aer Lingus and British Airways.
He also asked if the Irish Government sought assurances from IAG to ensure it will continue to work with partner airlines.
Mr Thompson also sought assurances regarding the preservation of connective competition and effective maintenance interline partnerships for passengers.
Earlier in the week IAG chief executive Willie Walsh said he would be "delighted" to see Virgin Atlantic granted its request to appear before the committee.
"It's not unusual for Virgin to see if they can get something out of a process so it didn't surprise me,” he said.
“But I think it would be very interesting for Virgin to appear before the Oireachtas Joint Committee on Transport and explain their interests in the Irish market given that they don't fly here.
"As far as I'm concerned or aware they've never shown any interest in flying to Ireland or in serving the Irish market," he said.