NEW DELHI- India is expanding a covert uranium enrichment plant that could potentially support the development of thermonuclear weapons, a defence research group said today, raising the stakes in an arms race with China and Pakistan.

The revelation highlights a lack of nuclear safeguards on India under new Prime Minister Narendra Modi, while sanctions-bound Iran faces minute scrutiny in talks with world powers over its own nuclear program.

New units at the Indian Rare Metals Plant would increase India's ability to produce weapons-grade uranium to twice the amount needed for its planned nuclear-powered submarine fleet.

The facility, located near Mysore in southern India, could be operational by mid-2015, the research group said, basing its findings on analysis of satellite imagery and public statements by Indian officials.

Unlike Iran, India is not a signatory to the nuclear Non-Proliferation Treaty. New Delhi tested its first nuclear weapon in 1974, provoking international sanctions that barred it from importing nuclear technology and materials.

Based on its analysis of commercial satellite images, IHS Jane's has identified what appears to be a new uranium hexafluoride plant that would increase the uranium enrichment capacity of the Mysore facility.

The plant would be able to produce a surplus of around 160 kilos a year of uranium enriched to 90 percent purity, IHS Jane's reckons. That is roughly double the needs of the nuclear submarine fleet India is developing to supplement its land-based missile arsenal - and enough to make five atomic bombs.