Israel has said it will not allow any refugees to cross the border, despite urgent calls by humanitarian agencies saying their safety is at risk.
"The bombardment started from 03.00 (midnight GMT) and continued for the last six hours", said Rami Abdel Rahman, the head of the Syrian Observatory for Human Rights.
"Around 800 missiles and shells have been fired against several areas in the province and fierce fighting continues on the ground between regime forces and rebels", the group's director said.
Shapiro writes that Trump seems "genuine in his commitment to Israel's security", while Putin "seems to take Israel's security concerns seriously", and that "Netanyahu has to be given considerable credit for his ability to maintain a respectful dialogue with Putin over the past three years, enabling Putin to understand Israel's security red lines in Syria and its determination to enforce them". The director did not immediately provide an estimate of casualties. Israel does not want its enemies Iran and Hezbollah, both allies of Syrian President Bashar al Assad, who are well entrenched in that area, to move forces near its border. The gains follow the full liberation of Dara'a city from extremist armed groups on Thursday.
Since June 19, the Syrian army has been conducting a liberation operation in Dara'a, which borders Jordan and the Golan Heights.
Syria's state television said on Monday that the army had taken control of al-Harah hill in the second day of a major offensive to seize the remaining militant-held parts of southwestern provinces. They've liberated a number of villages in the northwest of Dara'a province.
What's more, the bordering village of "Al-Sousah" also accepted the terms of negotiations with government.
The Observatory said an estimated 1,400 people were expected to be evacuated in a single group on Sunday.
Regime forces briefly overran the hilltop on Monday but an HTS ambush left 12 regime forces dead and forced them to retreat, Abdel Rahman said.
Moscow and Damascus reached a deal with rebels in early July for all of Daraa province, then agreed on terms for the city on Wednesday.
Under such agreements, rebel forces hand over territory as well as their heavy and medium weapons to regime troops in exchange for a halt to bombing.
Trump has shifted away from his predecessor Barack Obama's policy of demanding the ouster of Syrian leader Bashar al-Assad, a position the U.S. adopted before Russian Federation intervened militarily in late 2015 to turn the tide of the civil war in Assad's favour with Iran's help.
Syria's conflict has killed more than 350,000 people since March 2011, although the United Nations has long stopped keeping count of casualties in the seven-year conflict.