American Marconi Wireless News - Syrian conflict 'has not ended': UN

Geir Pedersen, the UN's special envoy for Syria, also called at the Security Council for Israel to "cease all settlement activity in the occupied Syrian Golan" and said an end to sanctions would be key to assisting the country.

Speaking about Turkish-backed and Kurdish fighters, Pedersen warned "there have been significant hostilities in the last two weeks, before a ceasefire was brokered."

"A five-day ceasefire has now expired and I am seriously concerned about reports of military escalation," he said.

"Such an escalation could be catastrophic."

Shortly after Pedersen spoke, the United States announced it had brokered an extension of a ceasefire, to the end of the week, between pro-Turkish fighters and Syrian Kurds at the flashpoint town of Manbij.

Pedersen also said he had met with Syria's new de facto leadership following the rebels' lightning takeover, and toured the infamous Sednaya prison's "dungeons" and "torture and execution chambers," operated under Assad's government.

He called for "broad support" for Syria and an end to sanctions to allow for reconstruction of the war-ravaged country.

"Concrete movement on an inclusive political transition will be key in ensuring Syria receives the economic support it needs," Pedersen said.

- Humanitarian needs -

"There is a clear international willingness to engage. The needs are immense and could only be addressed with broad support, including a smooth end to sanctions, appropriate action on designations, too, and full reconstruction," Pedersen added.

Western countries are wrestling with their approach to Hayat Tahrir al-Sham (HTS), which spearheaded the takeover of Damascus, and has roots in the Syrian branch of Al-Qaeda.

It has largely been designated in the West as a "terrorist" group, despite moderating its rhetoric.

The UN's new humanitarian chief Tom Fletcher warned that the seismic changes on the battlefield in Syria had done nothing to alleviate the dire situation facing the country's people.

"Nearly 13 million people were facing acute food insecurity. The recent escalation has only added to these needs. More than a million people were displaced in less than two weeks," he told the Security Council.

Fletcher also confirmed he had met Syria's new rulers and was "pleased to report that they have committed to what will be an ambitious scaling up of vital humanitarian support."

He also raised the alarm over the intensifying violence in the country's northeast, warning of "its potential humanitarian fallout" and saying it was a "case for concern and warrants urgent attention and efforts for de-escalation."

- Israeli incursions -

Pedersen noted Israel had conducted more than 350 strikes on Syria following the departure of Assad's government, including a major strike on Tartus.

"Such attacks place a battered civilian population at further risk and undermine the prospects of an orderly political transition," he said.

US ambassador to the UN Linda Thomas-Greenfield welcomed Assad's overthrow, but warned against the re-emergence of the Islamic State group, also known as ISIS.

"This is a historic opportunity for the long-suffering people of Syria to build a better life after more than a decade of conflict and corruption. Their needs are extensive, and the United States is committed to mobilizing global support," she said.

"There is a strong international consensus that Syria must not be used as a base for terrorists such as ISIS, (which) requires securing detention facilities and displaced persons camps in northeast Syria," Thomas-Greenfield said.

Pedersen meanwhile warned against plans announced by Israel's cabinet to expand settlements inside the Golan Heights, occupied by Israel since 1967 and annexed in 1981.

"Israel must cease all settlement activity in the occupied Syrian Golan, which are illegal. Attacks on Syria's sovereignty and territorial integrity must stop," he said.

J.Williams--AMWN