UNITED NATIONS - The United Nations is ready to work with the Syrian interim government on advancing towards a credible and inclusive political transition, a UN special envoy said on Wednesday.

"Today, Syria seeks to chart a new course following the fall of the former regime just one month ago. Decisions taken now will determine the future for a long time to come. There are great opportunities and real dangers," Geir Pedersen, UN special envoy for Syria, told the UN Security Council via video from Geneva.

"Syrians and the international community need to get the next phase right, and the UN stands ready to do everything we can to facilitate, to help and to support," he said.

Briefing the first Security Council meeting of the year on Syria, Pedersen said that the caretaker authorities continue to work to structure and consolidate their authority. They have held meetings with a very broad range of representatives and individuals of different Syrian groups and components, and met with visiting foreign ministers and officials.

However, he pointed out that there are signs of instability within areas under the control of the interim government, including reports of violence in the coastal region and Homs and Hama, and plans for public sector restructuring which may leave many without livelihoods.

Meanwhile, in the large areas outside the control of the authorities, the conflict continues, Pedersen said.

The special envoy called for and voiced his support for the further development of all channels of dialogue, and urged all parties to find a way forward without military confrontation.

Noting there are "very real threats" to Syria's sovereignty and territorial integrity, Pedersen listed Israeli military airstrikes and the terror group Islamic State.

Pedersen said he is "deeply concerned" by continued Israeli military presence and activity, including beyond the area of separation in violation of the 1974 Disengagement Agreement. Reports of Israeli forces using live ammunition against civilians, displacement and destruction of civilian infrastructure are also "very worrying".

"Such violations, along with Israeli airstrikes in other parts of Syria -- reported even last week in Aleppo -- could further jeopardize the prospects for an orderly political transition," the special envoy underscored, urging Israel to stop attack on Syria.

The United States on Monday issued sanction exemptions and waivers for transactions with Syrian governing institutions for six months in an effort to ease the flow of humanitarian assistance and allow some energy transactions, which was welcomed by Syria's interim Foreign Ministry.

Pedersen welcomed the move from the White House, adding "much more significant work in fully addressing sanctions and designations will inevitably be necessary".

"The way forward on political transition is unclear. There are positive elements to build on, but also points of concern that Syrians are expressing," he told the council.

"There are tremendous opportunities for building a foundation for lasting peace and stability in Syria. But missteps or missed opportunities could pose risks to Syria's future and plant seeds of instability," Pedersen said.