BEIRUT: The crisis in Syria is accelerating at an unprecedented pace unseen in recent years, the head of the United Nations High Commissioner for Refugees warned Friday in Beirut, and described the two-year-old conflict across the border as representing an “existential threat” to Lebanon.

“Two years after the beginning of the Syria crisis, we are witnessing the staggering escalation of the conflict that is accelerating the crisis in a way that is unprecedented in recent decades,” Antonio Guterres said at a news conference in the Lebanese capital.

Guterres, who kicked off a visit to Lebanon Thursday, also voiced alarm on the disparity between the needs of those suffering as a result of the Syria conflict and the available resources to assist them.

“There is a widening gap between the needs of the people suffering the impact of the Syrian crisis and the resources available to support [them],” he told a news conference at the Movenpick Hotel in Beirut.

“There is no way a gap of this magnitude can be filled with current humanitarian budgets,” he warned, adding: “We are not only witnessing a humanitarian tragedy but a threat to international peace and security.”

Guterres expressed hope that the funds pledged at a January conference in Kuwait would surface and be put toward the U.N. humanitarian response.

He said the gap between the money pledged and received stood at $700 million and stressed, saying that humanitarian organizations had received just a third of the funds needed to cover the basic needs of refugees.

“This is why I appeal to all governments and parliaments to approve extraordinary funds,” he said.

Gueterres also said crisis represented an “existential threat to Lebanon,” adding that this could only be countered through national solidarity.

Visiting Syrian families in the Chouf town of Ketermaya Thursday, Guterres pledged to ease the difficult refugee situation in Lebanon.

The U.N. High Commissioner for Refugees is aiding nearly 350,000 refugees in Lebanon, and the government, the U.N. and other aid organizations say the relief efforts are grossly underfunded.

Hundreds of millions of dollars of aid pledges by the international community have not been delivered, and Prime Minister Najib Mikati has recently called for Arab nations to do more to assist the refugees.