They have also warned of a statewide agitation in case their demands were not met.
Goa is having a water sharing dispute over the Mhadei river with Karnataka and Maharashtra.
The Mhadei Bachao Andolan, a green collective, held a press conference on Friday in Panaji in which it accused Chief Minister Pramod Sawant as well as Union Minister for Environment and Forests Prakash Javadekar of giving false assurances to the people of Goa over the central ministry's green clearance to Karnataka's Kalasa-Banduri project.
"The Mhadei Water Dispute Tribunal had directed the Central government to constitute a water management authority. Even the state government has not laid anything about the status of the Authority," Aam Aadmi Party's Goa convenor Elvis Gomes told reporters.
AAP is a part of the green collective specially founded to create awareness about the contentious Mhadei water diversion issue.
"Everything is being done behind a curtain to hide the sins of omissions and commissions by the government. The Andolan will become more aggressive if no steps are taken before Christmas begins," Gomes said.
In October, the Javadekar-led MoEF had given a green nod to Karnataka's Rs 841 crore Kalasa-Banduri dam project which aims to divert water from the Mhadei river basin to the water deficit basin of the Malaprabha river ostensibly for drinking water purposes.
After the Goa government and opposition parties pressurised the MoEF to withdraw the clearance, Javadekar had sought time to address the concerns. The Opposition as well as members of the collective have claimed that the MoEF's decision was "bad in law" and was taken with an eye on the 15 Assembly bypolls, which were held on December 5.
Former Goa RSS chief Subhash Velingkar, who is also a part of the collective, accused the Chief Minister of complete surrender before Karnataka, vis-a-vis the water diversion issue.
"This man calls Mhadei his mother. But the conduct of this so called son ready to sacrifice the life of this mother placing political interest above. It makes me say that it would have been better if Mhadei did not have such a son," Velingkar said.
Sawant has maintained that he would leave no stone unturned to ensure that Goa's interests are protected vis-a-vis the inter-state dispute.
The Mhadei river originates in Karnataka and meets the Arabian Sea near Panaji in Goa, while briefly flowing through Maharashtra.
An inter-state water disputes tribunal, set up by the Central government, after hearing the over two-decade-old Mhadei river water sharing dispute between Goa, Karnataka and Maharashtra, in August 2018 allotted 13.42 thousand million cubic feet (TMC) (including 3.9 TMC for diversion into the depleted Malaprabha river basin) to Karnataka and 1.33 TMC to Maharashtra.
( With inputs from IANS )