The Vietnam PM is on a two-day visit to India (Press Trust of India)

India is likely to provide four naval patrol vessels to Vietnam in a military transfer significant to Hanoi's attempts to improve its defence in the South China Sea, where it is embroiled in a territorial dispute with China.The four patrol ships will be provided to Vietnam under a $100 million defence credit line and represent a push by the government to counter Beijing's influence in South Asia by deepening ties with old ally Vietnam.Prime Minister Narendra Modi held talks with Vietnamese premier Nguyen Tan Dung on Tuesday.A government official said negotiations for the patrol craft have gathered pace since the credit line was announced last month during President Pranab Mukherjee's visit to Vietnam.Vietnam wants the craft for surveillance off its coast and around its military bases in the Spratly island chain in the South China Sea where it is building a credible naval deterrent to China with Kilo-class submarines from Russia.Indian officials say the offshore patrol vessels are dual purpose - they can be used for anti-piracy operations and military purposes.Claims by an increasingly assertive China over most of the energy-rich sea have set it directly against US allies Vietnam and the Philippines. Brunei, Taiwan and Malaysia also claim parts of the waters.India and Vietnam have a long-standing defence relationship but it has been restricted to military exchanges, training, spares and maintenance of military hardware since both have predominantly Soviet-origin equipment.

Training has moved to a higher gear since Vietnam acquired the diesel-electric Kilo submarines which India has operated since the 1980s. It has been giving underwater combat training to Vietnamese sailors at the submarine school, INS Satavahana, in Visakhapatnam since October.