Richard Branson has taken his battle against the proposed tie-up between British Airways and American Airlines to Barack Obama.

The Virgin Atlantic founder has written to the US President in the hope of persuading US administrations to block the transatlantic tie-up.

In his letter to the White House, the billionaire tells the US President that “now, more than ever, consumers are counting on you to put their interest first”.

Sir Richard argues that BA/AA is on “a different scale” to the Star and SkyTeam alliances that have immunity because of their dominant position at Heathrow.

He claims that, thanks to the scarcity or expense of slots at Heathrow, approving the BA/AA application for anti-trust immunity (ATI) would boost their dominant position even further.

“Never before has the US government approved an anti-trust immunity application where barriers to entry are so significant that any new meaningful competitive entry is virtually impossible,” he wrote.

“If their proposals were to be approved, AA-BA would have a monopoly, or near monopoly, on some of the busiest and most profitable routes from the US to Europe”, he told The Telegraph.

“AA-BA are seeking ATI authority to jointly set prices and co-ordinate capacity and schedules because it will enable them to squeeze existing US-Heathrow competitors off key routes. If AA-BA win, it will be an unprecedented loss for consumers.”