NEW DELHI, Sept 21 (Reuters) - India's cabinet cleared the purchase of 36 Rafale fighter jets from Dassault Aviation on Wednesday, paving the way for signing a deal that Prime Minister Narendra Modi is betting on to modernise the air force, a government source told Reuters.

The value of the deal, which had been repeatedly held up as the two sides haggled over financial terms, was not immediately available.

Under the deal, India will get 36 Rafale jets in fly-away condition. India's fighter aircraft fleet, comprising Russian, British and French planes, is down to 33 squadrons as against the air force's requirement of 45 to counter a "two-front collusive threat" from Pakistan and China.

The two countries will sign the final deal on Friday, the source, who did not wish to be named as he is not authorised to speak to the media, said. (Reporting by Nigam Prusty; Editing by Malini Menon)

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