EU regulators will decide by July whether to clear or block a plan by British Airways , American Airlines and Iberia to deepen their Oneworld alliance, the EU's antitrust chief said.

The European Commission is reviewing the results of a market test on concessions offered by the three companies last month to gain European Union antitrust immunity for their alliance.

Asked when a decision was expected, European Competition Commissioner Joaquin Almunia told Reuters on the sidelines of a briefing organised by the European Policy Centre think tank: "In June or July."

He had earlier told the briefing the Commission favoured mergers in the airline industry.

"The trend towards consolidation in this sector is a reality, one that we support," Almunia said.

"When analysing mergers and alliances in the sector, we are mindful of the benefits and scope for the industry in terms of international competition but also of the need to ensure that consumers do not pay the price for it."

The U.S. Department of Transportation gave tentative approval for the alliance in February. Airlines see such tie-ups as a lucrative alternative to mergers and large-scale investments.

The three companies have proposed giving up some landing and take-off slots for routes from London to Dallas, London to Boston, London to Miami and possibly London to New York if competitive conditions change.

They also want to allow access to their frequent flyer programmes on those routes as well as London-Chicago and Madrid-Miami and to submit data on their cooperation plan. Rival Virgin Atlantic opposes the strengthened alliance, saying the antitrust concessions are woefully inadequate. (Reuters)