"With deep sorrow we announce to the people of Tamil Eelam, the Tamil people living all over the world and the international community, that at 6 am today, head of our organisation's political wing Brig. S P Thamilselvan was killed by the Sri Lankan air force aerial bombing," the rebels said on their Web site www.ltteps.org.

Rebel aide Bawan, who works at Thamilselvan's peace secretariat in the northern rebel stronghold of Kilinochchi, confirmed the news by telephone to Reuters.

Thamilselvan was the rebels' main interlocutor at the last round of peace talks with the Sri Lankan government in Oct 2006, and was the international face of the separatist group led by shadowy rebel Velupillai Prabhakaran and widely outlawed as a terrorist organisation.

"The loss of Thamislevan in this way would be a very big setback to any hope of peace talks in the near future -- which in any case were not apparent either," said Jehan Perera of non-partisan advocacy group the National Peace Council.

"It just makes it an even bleaker scenario."