NEW DELHI: Domestic orders placed for the BrahMos missiles have been worth more than $7 billion over the last 20 years, and if exports fructify the sales could double in the next five years, BrahMos chief said on Monday.BrahMos Aerospace, an India-Russian joint venture formed in 1998, manufactures the supersonic cruise missile that can be launched from submarines, ships, aircraft, or land.While India could use the BrahMos missiles for its three services -- Army, Navy and the Air Force -- it could not export them before June, 2016, when it became a signatory to the Missile Technology Control Regime MTCR ).The MTCR membership enabled India to trade in high-end missile technology and also enhance its joint ventures with Russia "The journey of (nearly) 20 years has not been easy. We have struggled with our finances, technology, users. Challenges have been so many," BrahMos Aerospace's CEO Sudhir Kumar Mishra said speaking at the Deftech 2017, an event organised by the Confederation of Indian Industry and the Defence Ministry The company started making profit only in its 14th year, he said.Over a period of time, the missiles have been developed to become more effective for all the three services, he said."The journey has been meaningful because we invested $300 million and today we have orders worth more than $7 billion," Mishra said.After India joined the MTCR, many countries, especially Vietnam, expressed interest in buying the BrahMos missiles."If exports fructify, then this (the order for BrahMos missiles) can almost double in another five years," he said.Later, when asked about exports of the missiles, he declined to comment, saying he was not authorised to talk to the media and the Defence Ministry would be in a position to comment on it.In August, there were reports of India supplying BrahMos anti-ship cruise missiles to Vietnam. However, the information was dubbed "incorrect" by the Ministry of External Affairs.Speaking at the inaugural session of the programme, G Satheesh Reddy, the Scientific Advisor to the Defence Minister, said a strong research and development (R&D) base is necessary for making the country self-reliant in defence technology.