"We know that in Lebanon you have militias which are very heavily armed and increasingly so. This creates a hyper-dangerous situation," Terje Roed-Larsen, a special U.N. envoy told reporters in New York after briefing the U.N. Security Council in private.
Roed-Larsen called the combination of armed forces and political tensions in Lebanon "the most critical issue of international peace and security today," a U.N. release said.
"This is why all parties in Lebanon, in the region and beyond must now shoulder their responsibilities to stop irresponsible and reckless rhetoric," he said.
"Critical to this is also the disbanding and disarming of all militias. Militias holding arms in Lebanon today is an intimidation in itself, particularly when it is paired with reckless and irresponsible rhetoric."
In a report Roed-Larsen delivered to the Security Council, U.N. Secretary-General Ban Ki-moon called on all players to focus on strengthening Lebanon's sovereignty and security.
"The country should not be used as a staging ground for furthering regional aspirations or promoting conflict," Ban wrote.
Roed-Larsen said he believes the Middle East is at "an extremely critical juncture," with "crosswinds and a hurricane blowing up" in the region.
"And in the middle of those crosswinds, there is a tent standing, and that tent is critically upheld by two poles," he said. "One is the Palestinian one and the other one is the Lebanese. If one of those poles cracks, the whole tent will go down."
The report dealt with the status of Resolution 1559, which was adopted by the Security Council in 2004 and calls for free and fair elections, an end to foreign interference and the disbanding of all militias.