Russia is close to finalising a deal to build helicopters in India, an executive said Tuesday, a move that would boost Narendra Modi's ambitions to manufacture defence hardware locally.

India is the world's top defence importer and is seeking to revamp its Soviet-era military equipment against an increasingly assertive China.

Prime Minister Modi has been encouraging foreign firms to work with local contractors under a "Make in India" campaign, to reduce India's reliance on costly imports.

Russia and India first flagged plans for a joint partnership to build Kamov helicopters -- a twin-engine chopper used for military and civilian purposes -- in 2015.

But India has increasingly turned to the United States and France, rather than traditional ally Russia, for its military hardware in recent years.

Two Russian firms -- Russian Helicopters and state-owned arms exporter Rosoboronexport -- are on the brink of finalising a joint venture with India's state-run Hindustan Aeronautics Limited, according to reports.

Viktor Kladov from Rostec, the parent company of Rosoboronexport, said the joint venture would be completed in "one to two months".

"We have conducted multiple negotiations, most recently in January this year," Kladov was quoted as saying by the Press Trust of India news agency.

"The document work for the joint venture has been completed and they have been sent for registration with the relevant government bodies."

The helicopters will replace India's ageing fleet of Cheetah and Chetak helicopters.

President Vladimir Putin has been seeking to seal deals with India to help revive Russia's recession-hit economy, following sliding oil prices and Western sanctions over the Ukraine crisis.

Kladov said he hoped the Kamov choppers would eventually be exported to India's neighbours once the production line was up and running.

"These helicopters are versatile and modular, so they can be used in military, search and rescue, medical and transport tasks," he said.

"It is possible that the regional market, the neighbouring countries may be interested and the choppers can become export products on their own."