Virgin Atlantic announced yesterday that it is to undertake the first biofuel-powered test flight of one its Boeing 747s next month.

The demonstration flight from London Heathrow to Amsterdam, which will be undertaken with no passengers on board, will mark the first time a commercial aircraft runs using biofuel in-flight.

A spokeswoman for Virgin declined to identify the source of the biofuel that will be used in the flight, insisting that the project was still at the test phase and the biofuels being used would be announced in due course. However, she insisted that the fuel was genuinely "sustainable" and was not made from crops that compete with food and water resources.

Virgin president Sir Richard Branson said that the project, which has been developed in conjunction with Boeing and GE Aviation, would help the airline " fly its planes using clean fuel sooner than expected".

"The demonstration flight next month will give us crucial knowledge that we can use to dramatically reduce our carbon footprint," he added.

The test flight represents the latest milestone in Virgin's drive to position itself as a green airline. The company recently became the first to offer passengers to buy carbon offsets in-flight and also placed Europe's largest order for new Boeing 747 Dreamliners amid promises the aircraft would use 30 per cent less fuel than the Airbus A340-300 it will replace in Virgin Atlantic's fleet.

Branson has also pledged that all profits from Virgin Group's transportation companies will be invested in developing clean energy technologies.