India is in negotiations with Vietnam to seal the first ever defence deal with the Southeast Asian nation. The deal is for short range surface-to-air Akash missiles, the head of India’s defence research agency S. Christopher said on Wednesday.

“We are talking to countries, one of them is Vietnam,” he told a news conference on the sidelines of an air show where the Defence Research and Development Organisation (DRDO) is showcasing its missile programmes and other key projects, including a home-grown light combat fighter. Christopher did not provide any details of how many Akash missile batteries the government planned to supply Vietnam.

India in the past considered the sale of its Brahmos supersonic missile with a range of 290 kms to Vietnam and has been steadily helping Hanoi beef up its defence.

This deal is a step towards Prime Minister Narendra Modi’s plan to establish India as an arms exporter. Last year, Modi announced a $500 million credit line to Vietnam to buy defence equipment, on top of a $100 million given previously to help it buy patrol boats. The two sides have also agreed for training of Vietnamese air force pilots to operate Su-30 Russian fighter planes.

However, such deepening of ties with missile sales could draw criticism from China that has been locked in a territorial dispute with Vietnam in the South China Sea. The disputes include the islands, reefs, banks and other features of the South China Sea, including the Spratly and Paracel islands, and the various boundaries, including those in the Gulf of Tonkin.