AMMAN (Reuters) - Thousands of Syrians who had fled an army offensive in the southwest to gather near a border crossing with Jordan have gone back further into Syria.

Jordanian border crossing, Jaber is seen in the city of Mafraq, Jordan July 7, 2018. REUTERS/Muhammad Hamed

They had congregated in a zone near the Nassib-Jaber crossing. Anders Pedersen, the U.N. resident and humanitarian coordinator in Jordan said on Sunday that only about 150-200 people remained there.

Jordan and Israel have both said they would not let refugees in. They beefed up their borders and distributed some aid inside Syria.

It was not clear where in south Syria the displaced people were headed, but the movement came after the army recaptured the crossing and some rebels agreed a ceasefire deal in talks with Russian officers. Witnesses said they left the border for different parts of Deraa province where fighting has died down.

Syrian government forces, backed by Russia, deployed at the Nassib crossing a day earlier, seizing a vital trade route that insurgents held for three years.

A military media unit run by Iran-backed Hezbollah, the Syrian army’s ally, said troops fully secured the major highway stretching from Damascus to Amman on Sunday.

The army also marched into an air base near Deraa city, cutting off the insurgents inside the city from others in a swathe of territory further west.

The United Nations says the violence has uprooted more than 320,000 people in the past two weeks, the biggest exodus of the seven-year war.

Around 60,000 have sought shelter near the border with Jordan and thousands more at the frontier with the Israeli-occupied Golan Heights.

Pedersen called for access to Syria’s Deraa and Quneitra provinces, adding that an aid convoy was waiting to go to Mtaaiya village, which the army took in recent days.

“What we are asking for: unimpeded access” to southwest Syria, he told a news conference.

He said there were concerns about the safety of the displaced Syrians returning home.

Rebels in east Deraa have agreed to give up arms in a Russian-brokered ceasefire deal, handing another victory to President Bashar al-Assad’s state and its allies.

A Syrian military source said soldiers and allied forces gained control of Um al-Mayadan town in east Deraa on Sunday.

The Syrian Observatory for Human Rights, a UK-based war monitor, said Syrian and Russian air strikes pounded the town and its environs, killing three people.