Chennai: The DMK will be forced to consider withdrawing from the central government if it does not take decisive steps to stop attacks against Tamils in Sri Lanka and Indian fishermen allegedly by the island's defence establishment, Tamil Nadu Chief Minister M. Karunanidhi said Monday.

"The final decision in the matter will be taken by the DMK's highest policy making body - the general body," he said at a massive public meeting here.

Earlier in the day, his stand was firmed up on the issue of alleged attacks by the Sri Lankan military against Tamil minority targets in the island which he termed "genocide" and against its alleged killings of Indian fishermen in the Palk Strait.

During a telephonic conversation with Prime Minister Manmohan Singh, he demanded India lodge a strong protest with the island's diplomatic mission in New Delhi.

"The chief minister stressed that the Sri Lankan high commissioner be summoned and told that India condemns the genocide of the Tamil minority and (that) its navy is killing innocent Indian fishermen," an official note said. "The prime minister has promised to carry out the chief minister's wishes," it said.

"The prime minister was also requested to do the needful to ensure the immediate end of attacks on Indian fishermen at the hands of Sri Lanka's defence establishment," the statement added.

Karunanidhi opposed Saturday moves to involve the Indian and Sri Lankan navies to end the alleged killing of Indian fishermen in the narrow strip of water that separates the two nations.

Opposition leader and former chief minister J. Jayalalitha also demanded an immediate end to the killings of Tamils.

Except those belonging to the Congress and the Bharatiya Janata Party, politicians across the board in Tamil Nadu have objected to the Sri Lankan defence personnel allegedly killing Indian fishermen on the sea.