Sir Richard Branson has written to the two US presidential candidates asking them to stop any tie up between BA and American Airlines (AA).
The president Virgin Atlantic said any working together of the two carriers would not be in the consumers' interest.
Speaking on a UK radio programme today (August 11), Sir Richard if they got permission to work together, "the end result would be certainly higher fares for the consumer and massive job losses on both sides of the Atlantic."
He said he had written to Barack Obama, the Democratic runner, and John McCain, the Republican hope, asking them to oppose any link.
BA, AA and Spanish carrier Iberia have been in talks for sometime over a possible application to the US Department of Transportation (DoT) for anti-trust immunity.
BA declined to comment on reports that its representatives are due to meet DoT officials this week.
Sir Richard said that BA and American owned 70% of the slots at London Heathrow and were "completely dominant."
He said the competition authorities had twice told them that any tie up would be anti-competitive.
"Nothing in our opinion has changed and we are going to try very hard to try and stop it happening," he said.
He said the rise in the price of oil was not a reason to "rid yourself of competition."
During the interview, Sir Richard aid that Virgin Atlantic would announce a profitable year in its results at the end of August.
"We have had good passenger number and our profits are actually up and I think that is because we have a good quality service," he said.
But he described current market conditions as "as tough as we have ever known it" with the price of oil a "massive burden" for any airline.
He repeated that Virgin was still interested in a link with British Midland which would give the two carriers 15% of the slots at Heathrow.