European Commission opened its investigation into whether the transatlantic joint business agreement between American Airlines, British Airways and Iberia for flights violates European anti-trust regulations.

The trio applied two weeks ago for worldwide anti-trust immunity from the US Dept. of Transportation together with oneworld partners Royal Jordanian and Finnair.

An EC spokesperson said the probe is not the result of competitors' complaints and was launched under the regulator's own initiative.

"It's not a merger investigation and has no specific deadline," the spokesperson said.

Virgin Atlantic Airways, which has been a vocal opponent of the tie-up, said the EC investigation shows it "understand[s] that consumers will be worse off if this alliance proceeds."