Chennai, Apr 27 : Pushing forward his demand for an immediate ceasefire in Sri Lanka, Tamil Nadu Chief Minister M. Karunanidhi has gone on an indefinite fast here on Monday morning.

The 84-year-old Chief Minister sat on fast at the memorial of late C N Annadurai.

"Let me be one of Sri Lankan President Rajapakse''s victims. This is my sacrifice on behalf of all Tamils," Karunanidhi said.

Karunanidhi also said he did not want the Dravida Munnetra Kazhagam (DMK) men to go on a fast.

Karunanidhi''s daughter Kanimozhi and his grand nephew Kalanidhi Maran have gone to meet Karunanidhi, who recently underwent a major surgery for his back pain.

Union Minister K R Baalu and State Minister Arcot Veeraswamy were also among those present at the fast site. Earlier, the DMK supremo clarified that the priority was not to ban the Liberation Tigers of Tamil Eelam (LTTE), but to save the lives of thousands of Sri Lankan Tamils. In a telegram to Prime Minister Dr. Manmohan Singh, UPA chairperson Sonia Gandhi, External Affairs Minister Pranab Mukherjee, Karunanidhi had urged the Indian Government to issue a warning to Colombo to halt the war in Lanka immediately. He had also asked the UN and the international community to intervene in the matter. On Sunday evening, Tamil Tiger rebels fighting government forces in north-east Sri Lanka declared a unilateral ceasefire, following an "unprecedented humanitarian crisis".

Sri Lanka''s Defence Secretary Gotabaya Rajapaksa, however, dismissed the announcement as "a joke", insisting the rebels must surrender.

In a statement, the rebels said they were responding to "calls made by the UN, the EU, the governments of India and others".

They said the unilateral ceasefire would come into immediate effect.

According to the United Nations, some 50,000 civilians remain trapped but the army puts the number at 15,000.

Aid workers have been barred from the area since the fighting escalated last year.

The LTTE says the government is deliberately blocking food aid there - a charge the Sri Lankan authorities have denied. (ANI)