Tamil Nadu Chief Minister M Karunanidhi threatened on Thursday to boycott the talks with his Kerala [Images] counterpart V S Achuthanandan on the Mullaperiyar issue unless the Centre immediately stepped in to stop the neighbouring state's 'unlawful acts'.

The talks are scheduled to be in New Delhi on November 29.

Taking exception to the visit by 17 Naval officials to Mullaperiyar dam site on Thursday to check its safety following a request from Kerala government, he told reporters that it was Kerala's unilateral action without taking permission from Tamil Nadu which owns and maintains the dam.

"Any activity of this type is not in order when the Supreme Court itself has categorically observed that the dam is safe to store water upto 142 feet. The intimidating and precipitating action of Kerala government just on the eve of the talks between the states under the auspices of the Government of India is totally unwarranted and uncalled for," Karunanidhi said.

A letter has been written to Prime Minister Manmohan Singh [Images] demanding his immediate intervention to stop Kerala government's 'unlawful acts', he added.