New Delhi: India is in the final stages of negotiations with Vietnam for the export of BrahMos missiles, with only minor clearances remaining that are likely to be processed shortly, BrahMos chief Jaiteerth Joshi said on Thursday.The top scientist said work is also under way to further indigenise the missile, which is made in partnership with Russia, with efforts aimed at reducing costs by up to 20% over the next two years.Also Read: First desi BrahMos warhead delivered by private facility in Nagpur"Negotiations with Vietnam are almost final and only a minor clearance is left. It will be similar to the earlier exports to the Philippines. We are in talks with other countries (for exports) as well," Joshi told ET after flagging off the 100th BrahMos booster made by Solar Defence and Aerospace Ltd (SDAL).He said BrahMos plans to increase production capacity along with private sector partners that have received technology transfers for critical components such as the booster and warhead. Joshi also urged SDAL to scale up production to deliver at least 12 boosters a month. "The BrahMos booster is a technologically demanding system. Its realisation has required mastery over advanced materials, high energy propellant technologies, physical manufacturing processes and stringent quality assurance standards," he said.Joshi also flagged off the first BrahMos warhead made in India from the same facility. The warhead, manufactured by SDAL, is being shipped to the Terminal Ballistics Research Laboratory for testing, after which it will be certified for integration with the missile. At present, warheads are imported.Also Read: India, Russia developing smaller, hypersonic BrahMos: AlipovJoshi said work is under way on new variants of BrahMos, including a lighter NG version and an extended-range missile. He added that newer, longer-range missiles are likely to be ready in 3-4 years.