“Based on information that we have, there are reasons to believe that there is an increase of flow of arms both ways,” Terje Roed-Larsen, the UN special envoy to the Middle East, told reporters after briefing the 15-member UN Security Councilabout Lebanon.

According to the UN special envoy there are no specialized observers for this, but information is based on a variety of sources.

According to Roed-Larsen’s briefing notes, he told the council UN Secretary-General Ban Ki-moon had raised the issue of cross-border arms transfers with Lebanese officials during a recent visit to Beirut, urging them to improve border control, Reuters reported.

In late April, a ship bound for Syria loaded with three containers was detained by the Lebanese navy. The cargo vessel, which originated from Libya, was found on Saturday containing heavy machine guns, artillery shells, rockets, rocket launchers and other explosives

The UN special envoy stressed that the situation in Syria reminds us of Lebanon in the 1970′s.

“If you look at the situation in Syria, which is maybe the most likely that might spill over, then in a way it reminds us of the situation in Lebanon and in its neighbouring countries in the 1970s. And this is what I fear,” said the envoy.

Roed-Larsen said there was complete “uncertainty” over what will happen and that it was necessary for the UN Security Council to be ready to face the issue.

Meanwhile, Annan said, addressing the Security Council via videoconference in Geneva that there had been “a spate of bombings that are really worrying” and that the UN mission, mandated with monitoring a April 12 ceasefire in the country, was “the only remaining chance to stabilise the country”.

The international envoy tasked with bringing an end to the violence in Syria , said his six-point peace plan is a “possible last chance to avoid civil war.”

Annan told the UN Security Council he planned to carry out a second trip to Syria since he was named special envoy.

There are only around 60 UN observers in Syria, although the team is expected to grow to 300 in the coming weeks. The UN says it has registered more than 24,000 Syrian refugees in Lebanon, while activists say there are more than 30,000.