"It has led to disappointment on both sides. It has a negative impact and has also reignited old suspicions against India with the possibility of a backlash," Rizvi said while delivering the annual Sarat Chandra Bose Memorial Lecture on Indo-Bangla relations.
Stating that the cost of missed opportunity during Prime Minister Manmohan Singh's Dhaka visit last year is 'too frightening too imagine', he said the failure has also slowed down the progress so far achieved in bilateral relations.
The treaty was put on hold after West Bengal Chief Minister Mamata Banerjee had expressed reservations.
Rizvi, also a historian and scholar, said agreement should be made on the basis of equability, sustainability and legitimate demands.
Pointing out that there was progress on other areas like demarcation of land boundaries, he said, "Hope springs eternal that the right thing will be done. But the window of opportunity is getting smaller. This is the moment for action."
He said that a 'misplaced decision' was taken to divert Ganga water affecting farmers in Bangladesh.
But after the Sheikh Hasina government came to power in 2009, improvement of relations with India topped the agenda, he said, adding that killings in border areas was one of the issues taken up.
"We have been demanding zero border killing which has not yet been realised. The government is not satisfied," he said.
