BANGALORE (PTI): Hindustan Aeronautics Limited and Russia's United Aircraft Corporation (UAC) inked a pact to jointly develop and produce a fifth generation fighter aircraft, a top HAL official said today.

"We (HAL and UAC) are moving forward as per schedule. We (have) just done the general contract yesterday. I went to Delhi and signed the general contract," HAL Chairman Ashok K Baweja said.

HAL officials noted that under a preliminary inter-governmental agreement signed in October last year, the advanced multi-role fighter is being developed by Sukhoi, part of UAC, along with the Bangalore-headquartered defence PSU.

According to reports, Russia and India would simultaneously develop two versions of the aircraft -- a two-seat version to meet the requirements of India and a single seat version for Russian Air Force.

UAC had begun building a prototype of the jet fighter which would feature high manoeuvrability and stealth to ensure air superiority and precision in destroying ground and sea targets, reports said.

Asked about the proposed investment in the venture, Baweja said it was very difficult to say at this stage and added: "It will be quite a lot".

He told reporters on the sidelines of the celebrations of HAL Day that the Navratna company has put on the backburner its MRO (maintenance, repair and overhaul of civil aircraft) venture plans at HAL airport following a slowdown in the world civil aviation market.