Tamil Nadu Chief Minister M Karunanidhi on Thursday requested Prime Minister Manmohan Singh to withdraw the Centre’s approval to Kerala for conducting a survey to build a new dam across the inter-state Mullaperiyar river, over which the state has moved the Supreme Court.

In a letter to Mr. Singh, Mr. Karunanidhi questioned the jurisdiction of the meeting of the standing committee of National Board for wildlife, which granted permission for the survey, to decide on the strength of the 112-year-old dam.

Mr. Karunanidhi said an expert committee, constituted by the Centre, had certified that the dam was safe.

The decision to permit a survey was taken based on ’erroneous’ details of the National Board for Wildlife and Union Minister of State for Environment and Forests Jairam Ramesh should order withdrawal of the permission, he said.

Mr. Karunanidhi said Tamil Nadu was left with no recourse except to approach the Supreme Court on Wednesday, seeking a stay on the Centre’s permission for the survey.

He said the Wildlife board had stated that the matter was not sub-judice, which was a ‘blatant misrepresentation of facts’ as the case was pending before the Supreme Court.

Tamil Nadu is locked in a dispute with Kerala, whose plans for construction of a new dam, is being opposed by it.

Kerala feels the present structure in Idukki District was unsafe.

But, Tamil Nadu contends that the present dam, under its control, was strong enough and wants to increase the storage level to 142 feet from 136 feet.