Norwegian mediators say they are pondering their future role in Sri Lanka's peace process, and have asked the government and Tamil Tiger rebels to clarify if they remain committed to a four-year truce that halted ethnic fighting in the country. While the Sri Lanka government says it is committed to peace efforts, the rebels have yet to respond to Norway's demand.

The talks in Oslo between Sri Lankan government and the Tamil Tigers were to be held Thursday to discuss the safety of the monitors who oversee a fragile truce. But in a surprise move, the rebels refused to meet the government delegates.

Instead, the rebels informed Norwegian mediators they would not accept cease-fire monitors from countries that are members of the European Union, which recently listed the rebels as terrorists. Two-thirds of the monitors come from EU countries, and will not be easy to replace.

Norway helped mediate the 2002 truce that halted ethnic fighting in the country, and has been on the frontlines of trying to keep the faltering peace process from falling apart.

But after the breakdown of Thursday's talks, Norwegian mediators are pondering their role in the peace process. They have asked the Tamil rebels and the government if they remain committed to the cease-fire, whether they want international truce monitors, and if they can guarantee the monitors' safety.

The Sri Lankan government says it is committed to the truce, and wants EU monitors to continue, despite objections from the Tamil Tigers, also known as the L.T.T.E.

"The European Union, despite the imposition of the ban, has taken the position that they will continue to engage with the L.T.T.E. as far as the peace process is concerned," said Ketesh Loganathan, the deputy head of the government peace secretariat. "So, we see this as no reason as to why the monitors who are from the EU countries cannot function."

The Norwegians have blamed the Tamil rebels for the collapse of the talks, which were called after an attack last month on a navy convoy carrying the truce observers.

Several political analysts have expressed fears that the refusal of the rebels to meet the government and accept EU monitors signals that the rebels are no longer committed to the peace process.

The truce is already under extreme strain. Daily attacks by both sides have killed more than 650 people since December.

The Tamil Tigers waged a deadly war for a homeland in the north and east of the country for the Tamil minority community until the 2002 truce.