SIR Richard Branson is set to air his grievances on the proposed tie-up between British Airways (BA) and American Airlines (AA) in the US next month, appearing in front of a key panel examining competition policy. <br /><br />The founder of Virgin group, who has been very vocal in his condemnation of the tie-up, was summoned as a witness for the House of Representatives Judiciary Subcommittee last week. He is set to give his views on the planned alliance on 16 September.<br /><br />The opposition to BA’s intentions to expand comes almost a year to the day after the airline announced plans to create an alliance with AA.<br /><br />The ailing British flag carrier is also in intense talks with the Spanish airline Iberia on plans to combine revenues and co-ordinate long-haul flights. <br /><br />The US Department of Transportation (DoT) is considering whether to grant BA and AA anti-trust immunity, which will let the two airlines complete the agreement.<br /><br />Sir Richard has dubbed the proposed venture a "monster monopoly", and has expressed concerns over the dominance it would have over Heathrow–US flights. <br /><br />“A tie-up would give the airlines an 80 per cent market share between Heathrow and Boston, for example,” a Virgin spokesperson said yesterday.<br />BA reported record full-year losses earlier this year, and a pre-tax loss of £148m in its first quarter.<br /><br />A spokesperson for the airline said yesterday that “BA is not aware of the details of any forthcoming hearings,” and added that the hearing was an investigation into all competition policy, not just the proposed deal between BA and AA.