The United Nations is to reduce its number of monitors in Syria from Thursday as violence across the country continues.
A spokeswoman for the UN Supervision Mission in Syria (UNSMIS) told Sky News that activities for all the remaining observers remain suspended.
Sausan Ghosheh said: "We will be down to 150 military observers tomorrow.
"The mandate of UNSMIS specifies up to 300 military observers. It was agreed with the Troop Contributing Countries that those observers who went home will be available to come back immediately if and when we resume our activities."
The monitors had their mandate extended for 30 days last weekend.
They are supposed to monitor a ceasefire and manage a transitional peace process devised by former UN Secretary General Kofi Annan.
But the peace process is non-existent and most populated areas of the country are now seeing significant violence.
Ms Ghosheh said: "UNSMIS activities are still suspended.
"We do undertake Special Integrated fact finding patrols, in places where there are ceasefires.
"We also do patrols that assess the impact of violence on civilians, such as visiting hospitals and IDP [Internally Displaced Persons] camps."
The humanitarian crisis is worsening significantly.
In an interview with Sky's Boulton & Co, the UN High Commissioner for refugees, Antonio Guterres, said that his organisation had seen a marked increase in population displacement.
He said: "Just to give you an idea, on Wednesday and Thursday, 15,000 people crossed the border into Lebanon; [on] Monday 6,000 people crossed; yesterday 400 per hour, which means we are now seeing a dramatic increase in the number of people fleeing the country.
"We are extremely worried the flows of people fleeing the country will also dramatically increase."
Meanwhile, Turkey has announced that it will shut all its borders with Syria, citing security concerns.
Crossings at Cilvegozu, Oncupinar and Karkamis along the Turkish border are all said to be closed.
However, many of those fleeing the violence are using a multitude of old smuggler routes to cross into Turkey, Lebanon, Iraq or Jordan.