Indian Air Force's attempts to bridge the growing gap in its fighting prowess is running into rough weather. The upgradation programme of the MiG-21 fighters, which would have allowed IAF same breathing space to tide over the crisis of plunging fighter squadron strength, is running late.

The Cabinet Committee on Security, which met in New Delhi late Thursday night, was informed that the upgradation programme is facing time overruns and the CCS sanctioned more funds to cover additional expenditure, sources said.

The IAF fighter strength would plunge to an all-time low of 29 squadrons by 2007 as more and more of the ageing MiG-21, the IAF's mainstay, are phased out.

As an interim measure to keep up its fighter squadron, till the acquisition of 126 multi-role fighters, IAF had commenced a programme to upgrade 125 MiG-21 fighters with enhanced avionics and weapons systems and all the modernised fighters were to enter service by 2007.

But now the CCS has been informed that there could be further delay of one to two years till all the fighters are inducted into the IAF. The sources said of the 125 fighters being upgraded so far only 85 have been inducted into the force constituting six of the ten squadrons being modernised.