Pakistan has issued the threat in a recent letter to India, the third such communication in last one year, official sources said.

In the letter, Pakistan has said the Indus Water Treaty, which governs sharing of six common river waters, is being violated by the Kishenganga project and it has the "right" to move the World Bank for arbitration, they said.

Pakistan's fresh threat comes after several rounds of bilateral talks failed to end differences over the issue.

Under the Treaty, World Bank is an arbitrator in disputes between India and Pakistan over sharing of river water and it can be invoked by either country.

Pakistan has been opposing construction of the power project on Kishenganga, claiming it violates the Indus Water Treaty, a contention rejected by India.

Work on the 330-MW project, capacity of which can be raised to 990 MW, started in 1994 and Pakistan immediately protested, prompting talks between the two countries to resolve it.

Under the Indus Water Treaty, Pakistan has exclusive right over three of the common rivers -- Indus, Jhelum and Chenab -- while India has exclusive right over Sutlej, Ravi and Beas. Kishenganga is a tributary of Jhelum river.
Pakistan has been alleging the diversion of flow will adversely affect its agriculture and hydroelectric project on river Neelam -- as Jhelum is known across the border.