“Punjab law terminating water sharing agreement with other states stands invalid,” the apex court ruled.
Haryana had approached the apex court after Punjab refused to share water with it.
At the root of the Punjab-Haryana dispute is water, an emotive issue in the Akali Dal-BJP-ruled Punjab where elections are due early next year.
Following the verdict going against Punjab, state Congress chief Amarinder Singh and 46 party legislators offered their resignations. Singh also resigned as Lok Sabha MP protesting the court’s verdict.
On November 1, Punjab Chief Minister Parkash Singh Badal had said Punjab will not accept any verdict against the state's interest on river waters.
"We are ready to make any sacrifice to safeguard the legitimate share of river waters," Parkash had said.
The Congress was in power in Punjab in 1982 when Indira Gandhi flagged off the project. The state government later carried out phased acquisition of 5,376 acres for constructing the main and minor canals to link the two rivers.
Haryana has completed the 90km-odd stretch of the main canal starting from Ambala to Karnal through Kurukshetra. The project, however, got stalled on the Punjab side during the Khalistan movement. In 2004 the then Amarinder regime passed the Punjab Termination of Agreement Act, 2004, that stopped construction of the SYL canal, prompting Haryana to move court.
In March this year, the Badal government decided to de-notify the 5,376 acres acquired for the project with the passage of the Punjab Sutlej-Yamuna Link Land (Return of Property Rights) Bill, 2016, to facilitate the return of 3,928 acres to villagers, sparking fresh protests from Haryana.