Pedersen said the United Nations organizations need to respond to the populations in southwest Syria, especially the displaced returning home from the Jordanian border and from near the Golan Heights, where they have fled airstrikes and shelling in the past weeks.
All areas along the Syrian-Jordanian border will be under the direct control of Syrian government forces, SANA reported.
At a meeting between rebel and Russian negotiators on Wednesday, Moscow insisted opposition factions hand over their heavy weapons in one go, while rebels wanted to do so in several phases.
The offices of the Syrian border control and customs were largely damaged.
The negotiating sides are also in disagreement over the issue of the rebels handing over their heavy weapons with Russian Federation insisting that they give up the entirety of their arsenal in one go and rebels wanting to do so in several phases. More than 320,000 people are now displaced.
In one village, Saida, there were few residents two days after Syrian soldiers captured it from the rebels. They rampaged through administrative buildings, ripping down the Syrian state flag and stomping on pictures of Syrian President Bashar Assad. The Syrian flag flew in the distance, along with what appeared to be a Russian flag.
Daraa has a symbolic significance as it was the birthplace of the Syrian war that erupted in 2011.
Both Damascus and Moscow have repeatedly denied the accusations. A war monitor said that the regime now controls about 70 percent of Daraa province.
They resumed talks at around midday on Friday.
Civil-defense sources in Daraa have told Anadolu Agency that the number displaced Syrians fleeing the area had surpassed 350,000.
Ahead of the crisis, the crossing was the busiest border crossing in Syria as it is situated on the Damascus-Amman global highway near Nasib.
The crossing was once a bustling and vital artery through which Syria exported goods to Jordan and from there on to oil-rich Gulf countries.
It also clears the path for reopening the Nassib crossing, an important economic passageway whose loss had impoverished both Syria and Jordan.
Reports also said that the losses of the Jordanian transportation sector as a result of the border closure is estimated at around half a billion US dollars.
On June 12, the Syrian regime - supported by Iranian militia groups and Russian air power - launched a wide-ranging operation aimed at capturing opposition-held parts of southern Syria.
Fighters who reject the agreement will be evacuated with their families to the rebel-held northwestern province of Idlib, it added.
Earlier Friday, the government-controlled Central Military Media said government forces now control most of the towns and villages on the eastern side of southern Daraa province.
The Syrian Arab Red Crescent (SARC) said a convoy of food parcels and flour bags, from the UN's World Food Programme, headed to Ibta town which came under regime army control last week.
Tense talks focused on the fate of Daraa city and its western countryside dragged late into Friday, said rebel spokesman Abazeed.
Calm reigned over the region on Saturday as the two sides finalised the ceasefire deal, according to the Syrian Observatory for Human Rights, a Britain-based monitoring group.