With the Centre yet to notify the Cauvery Management Board, Karnataka's decision to construct the reservoir was 'unacceptable to anyone,' TNCC President E V K S Elangovan said in a statement here.
"The unilateral decision to construct the check dam without getting Union Environmental Ministry's clearance is condemnable," he said.
He also refuted criticism that his party was adopting double standards on inter-state river disputes, saying it was as committed to the welfare of the state as any other political party.
He extended Congress' support to a bandh called by farmers' associations on March 28 protesting against Karnataka and the Centre over the dam issue.