Mr Thiruchelvam's coffin was taken from his home to a cremation-ground amid tight security.

Mr Thiruchelvam, of the Tamil United Liberation Front (TULF), was in his car near his office in Colombo on Thursday when a man threw himself at the vehicle, detonating an explosion which killed them both. Five others were wounded.

Mr Thiruchelvam - an adviser to President Chandrika Kumeratunga - had been working on a devolution plan for the Tamil community, which was opposed by the separatist Tamil Tigers.

The plan was due to be presented to the Sri Lankan parliament next month.

Police believe the Tigers were behind the bomb attack in which Mr Thiruchelvam died.

International condemnation

Among those who paid tribute to Mr Thiruchelvam's efforts to restore peace to Sri Lanka was President Clinton, whose message said a "powerful voice for reconciliation" had been silenced.

UN Secretary-General Kofi Annan's message - also read out at the funeral - praised the Tamil MP's involvement in constitutional reform and said he had "tirelessly defended human rights" and contributed to the search for a political solution to the conflict in Sri Lanka.

The UN Human Rights Commissioner, Mary Robinson, called Mr Thiruchelvam's killing "a direct attack on efforts to bring about reconciliation and build a culture of peace and respect for fundamental rights in Sri Lanka".

"Sri Lanka and the world have lost a voice that rang loud and strong in defence of human rights," her message said.