The French and Indian defence ministers agreed to press ahead with negotiations on the sale of 126 Rafale fighter jets to India, both sides said Tuesday, after slow progress cast doubt on the estimated $12 billion deal.

Successive deadlines to complete one of the world's biggest airline contracts have slipped by, leading to reports that Britain's Eurofighter could try to re-enter the race.

French Defence Minister Jean-Yves Le Drian said negotiations were "proceeding well" after he met his newly appointed Indian counterpart Manohar Parrikar in New Delhi on Monday.

"For a project of this scale and such complexity... the pace is comparable to that of other negotiations," he said in an interview with Indian daily The Pioneer Tuesday.

"Both our governments share the will to conclude it (Rafale deal) and this is, of course, essential."

The pair discussed "all issues including Rafale", an Indian defence ministry spokesman told AFP.

"It was decided that whatever differences still existed would be resolved in a fast-track manner."

French company Dassault Aviation won the right in 2012 to enter exclusive negotiations with India to supply 126 fighters after lodging a lower bid than rival firm Eurofighter.

The deal would see Dassault supply 18 Rafales -- twin-engine multi-role fighters -- by 2015.

India, the world's top weapons importer, is in the midst of a $100-billion defence upgrade programme and experts say it urgently needs the jet fighters to maintain a combat edge over nuclear rival Pakistan.

The remaining 108 would be made by state-run Hindustan Aeronautics Ltd under technology transfer agreements with India, which is keen to boost homemade defence manufacturing.