NEW YORK - Arms smuggled from Syria to Lebanon that reach the Palestinian refugee camps constitute a central threat to the stability of Lebanon and a danger to its sovereignty. This is believed to be the gist of a report due to be published Monday at UN headquarters, compiled by the UN special envoy to the Middle East, Terje Roed-Larsen, with a view to the implementation of Security Council Resolution 1559.

Sources in New York say the report will demand unambiguously of the Lebanese government to take immediate and effective action to stem the flow of arms, which serve as the main weapons for the Palestinian militias, into the country.

UN Secretary-General Kofi Annan will decide when the report's contents are to be made public. According to UN sources, it could be only during his upcoming visit to Europe later this week.

Roed-Larsen presents a similar report every six months to the Security Council. Senior diplomatic sources at the UN said categorically Thursday that Roed-Larsen's report should not be seen as an attack on Syria in the wake of the findings of the Mehlis report last week on the assassination of former Lebanese premier Rafik Hariri. But Roed-Larsen does believe disarming Hezbollah is of prime importance, they said.

"Larsen's mandate is to examine what is going on in Lebanon," a source added. "It concentrates on the implementation of resolution 1559."

Diplomatic sources in New York said, however, that the report hints at dissatisfaction with Syria's involvement in internal Lebanese affairs. Roed-Larsen reportedly states explicitly that Hariri's murderers must be exposed as soon as possible.

Resolution 1559 was adopted in September 2004 and does not mention Syria by name but calls for all foreign forces to leave Lebanon. It also calls on all UN members to uphold Lebanon's sovereignty and political integrity. The resolution likewise urges the Lebanese government to step up the process of establishing its authority over the entire country and disarming the militias.

In his report, Larsen is believed to state that Hezbollah does not have anything to oppose and therefore there is no reason for the organization to retain its arms.

The Security Council is expected to respond officially to the Larsen report - either in the form of a declaration by its president or in a special resolution.