Industry sources told Reuters earlier on Monday that Airbus would announce a partial redesign of the jet, increasing the maximum amount of fuel or payload at take-off to extend its range.

The 240 tonne A330-300 will now be able to fly up to 11,020 km, while the new A330-200 will fly to a range of 13,060 km, Airbus said.

This means, for example, that the A330-300 can now connect new city pairs like London to Tokyo, Frankfurt to Cape Town, or Beijing to Melbourne.

Airbus is revamping the A330 at a time when arch-rival Boeing is pondering a new competing version of its 787 Dreamliner.

Airbus said it hoped to announce a customer for the enhanced A330, due to come into service in mid-2015, during this week's airshow.

"We've already had three airlines and one leasing company saying 'Can't you get it for early 2015'," Airbus sales chief John Leahy told journalists.

"We could maybe get it a few months early but summer 2015 is target for now," he said.

Leahy also said the A330 would be in production alongside the A350, and that the A330 would not be retired for many years yet. "I'll be in retirement by the time the A330 is retired," Leahy said.