Virgin Group owner Richard Branson has slammed a $270-million acquisition deal by rival company International Airlines Group (IAG), saying that the approval of the deal will mean higher prices for flyers.

IAG, which was formed by the merger of British Airways and Iberia, has earlier announced that it has reached a binding agreement to acquire Deutsche Lufthansa AG's unprofitable airline British Midland International, or BMI.

The agreement is aimed at promoting the expansion of IAG at the congested Heathrow airport in London.

Buying BMI's mainline business gives IAG a unique opportunity to grow at Heathrow, one of our key hub airports. Using the slot portfolio more efficiently provides the option to launch new longhaul routes to key trading nations while supporting our broad domestic and shorthaul network, IAG chief executive Willie Walsh said in a statement.

Once the deal is passed, IAG's percentage of the takeoff and landing slots at Heathrow will increase from 10 percent to about 53 percent. With this, the group which had earlier reported a loss of $201 million for the first nine months of the year will establish its position as the most powerful carrier at the airport.

However, business magnate, Richard Branson who made a rival bid for BMI, is reportedly furious over this and will ask authorities to stop the transaction in order to prevent this monopoly.

BA is already dominant at Heathrow and their removal of BMI just tightens their stranglehold at the world's busiest international airport. We will fight this monopoly every step of the way as we think it is bad for the consumer, bad for the industry and bad for Britain, said Branson.

At the Heathrow Airport, Virgin Atlantic controls just 3 percent of the total slot.