India had hit back, condemning Pakistan's action.
India has rejected Pakistan Prime Minister Shehbaz Sharif's allegation that New Delhi's decision to put Indus Water Treaty in abeyance is "illegal".
Talking exclusively to NDTV, Jalshakti Ministry's Adviser on Indus Water Treaty and former Commissioner (Indus) Kushvinder Vohra said India's decision to put the Indus Water Treaty in abeyance is "legally valid as per the prevailing international laws".
"The Vienna Convention on International Treaties is not strictly applicable on the Indus Water Treaty as it became effective only in 1980 and the treaties made before 1980 does not come under its ambit. IWT was signed in 1960," he said.
Nevertheless, even as per convention, when fundamental circumstances change, the Indus Water Treaty can be suspended or abrogated as may be the situation, Mr Vohra explained.
"India has used its rights to put the treaty in abeyance since Pakistan has consistently acted against the spirit of goodwill and friendship which was the cornerstone of Indus Water Treaty," he said.
Under these circumstances, even if Pakistan goes to international forums to challenge India's decision, its case will not stand because there are fundamental changes in circumstances, especially in terms of Islamabad acting against the spirit of goodwill and friendship, technological changes, climate change effects among others, he added.
On Friday, Pakistan Prime Minister Shehbaz Sharif had said at an international conference that his country would not allow India to cross the red line by holding the Indus Waters Treaty in abeyance and endangering millions of lives for narrow political gains.
India had hit back, condemning Pakistan's action.
At a UN conference on glaciers in Tajikistan's Dushanbe, Minister of State for Environment Kirti Vardhan Singh said Pakistan was violating the treaty through terrorism. "Pakistan, which itself is in violation of the treaty, should desist from putting the blame of the breach of the treaty on India," he said.
The treaty's preamble says it was concluded in the spirit of goodwill and friendship, and honouring the treaty in good faith is essential, he had added.
The Indus Waters Treaty, signed in 1960 between India and Pakistan with the World Bank as a signatory, governs the sharing of the Indus river system's waters between the two countries. India put a freeze on it after the terror attack on tourists in Pahalgam on April 22 in which 26 people died.
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