India has issued a notice to Pakistan for modification of the Indus Waters Treaty (IWT) of September 1960 following Islamabad's "intransigence" on its implementation, government sources said on Friday. The notice was sent on January 25 through respective commissioners for Indus waters, they said.

India is seeking modifications in the treaty to make it easier for Pakistan to enter into intergovernmental negotiations, within 90 days, and rectify the 'material breach' of IWT. This process would also update IWT to incorporate the lessons learned over the last 62 years.

"However, Pakistan's actions have adversely impinged on the provisions of IWT and their implementation, and forced India to issue an appropriate notice for modification of the pact," said a source.

The Indian side says it was forced to make the move after Pakistan took unilateral action for examining its objections to India’s HEPs. In 2015, Pakistan first requested for appointment of a neutral expert to examine its technical objections to India’s Kishenganga and Ratle Hydro Electric Projects. In 2016, it unilaterally retracted this request and proposed that a Court of Arbitration adjudicate on its objections.

Accordingly, India made a separate request for the matter to be referred to a neutral expert.

The treaty sets out a mechanism for cooperation and information exchange between the two countries regarding use of waters of a number of rivers.