The chief of the monitoring mission, Hagrup Haukland, met Friday with the government's top official in the peace process, Jayantha Dhanapala, and handed over a Tamil Tiger proposal to step up protection.

The Tigers demanded that soldiers be present in all vehicles transporting guerrillas to guarantee their security. They also asked for larger groups to be divided up and transported in separate vehicles.

"We are very much concerned about the cease-fire and the peace process," Haukland said. "The climate between the parties, in relation to this issue (guards for the rebels), is not good at all."

After talks with Haukland on Thursday, Tiger political chief S P Thamilselvan said he had demanded that the government boost security for rebels traveling in the island's restive east within two weeks -- or risk the collapse of the February 2002 cease-fire that ended this country's brutal two-decade civil war.

"If the LTTE [Images] decides to use its own armed escort, the cease-fire agreement will likely collapse," Thamilselvan said, using the acronym for the rebels' official name, the Liberation Tigers of Tamileelam.

Since the February 2002 truce, the military has provided escorts for rebels traveling through government-controlled territory in Sri Lanka's volatile east, parts of which are under guerrilla control.

But the rebels want more and better protection, "in the absence of which, LTTE would resort to its own pre-cease-fire arrangement that would entail confrontations putting the cease-fire agreement at serious risk," Thamilselvan said.

The Tigers' warning came four days after a bomb blast narrowly missed a bus carrying 41 rebels. Shrapnel injured one of the guerrillas.

The Tamil Tigers began fighting in 1983 to carve a separate homeland for minority ethnic Tamils in the country's north and east, claiming discrimination by the majority Sinhalese.

The conflict killed nearly 65,000 people before the 2002 truce. Subsequent peace talks broke down in 2003 due to disagreements about postwar power-sharing.

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