The blistering onslaught has prompted outrage against the regime, with the UN’s human rights chief saying the government was orchestrating an “apocalypse” in Syria.
The Russia-backed Syrian regime forces and allied militia launched an offensive on Feb. 18 to retake the last opposition bastion near Damascus.
They have since taken more than 40 percent of the enclave, waging a devastating bombing campaign that has killed more than 800 civilians.
Heavy airstrikes battered several key towns in the zone on Wednesday, as the Syrian regime dispatched hundreds of pro-regime militiamen to the front.
“At least 700 Afghan, Palestinian, and Syrian loyalist militiamen came from Aleppo and were sent late on Tuesday to Ghouta,” said Rami Abdel Rahman, head of the Syrian Observatory for Human Rights.
The Britain-based war monitor said the reinforcements were deployed to two main battlefronts on the western side of the enclave, including the town of Harasta.
Regime troops on Wednesday were within firing range of the key towns of Misraba and Beit Sawa, and had taken up positions at the edges of Jisreen and Hammuriyeh.
Three civilians including one child were killed in heavy airstrikes on Jisreen on Wednesday, the Observatory said.
That brought the toll in more than two weeks of bombing to 810 civilians, including 179 children.
Syria’s state television on Wednesday morning showed a live broadcast of farmland adjacent to Misraba, with columns of smoke emerging from the town’s skyline.
The bombardment has continued despite a one-month cease-fire demanded by the UN Security Council more than a week ago.
UN human rights chief Zeid Ra’ad Al-Hussein said the Syrian regime and its foreign allies were already planning their next “apocalypse.”
“This month, it is Eastern Ghouta which is, in the words of the secretary-general, hell on earth; next month or the month after, it will be somewhere else where people face an apocalypse — an apocalypse intended, planned and executed by individuals within the government, apparently with the full backing of some of their foreign supporters,” said Hussein.
Eastern Ghouta’s roughly 400,000 residents have lived under government siege since 2013, facing severe shortages of food and medicines even before the latest offensive began.
Forty-six aid trucks entered the area on Monday for the first time since the offensive, but had to cut short their deliveries and leave due to heavy bombardment.
Nearly half of the food aid could not be delivered and Syrian authorities removed some medical and health supplies from the trucks, the UN said.
Secretary-General Antonio Guterres urged all warring sides to allow aid trucks to return for a planned second delivery to the enclave's main town of Douma on Thursday.
Meanwhile, also on Wednesday Syrian refugees and German politicians condemned a visit to Damascus by members of an anti-immigrant party, saying their depictions of life in the city as “normal” were especially offensive when Ghouta was being bombarded.
Seven members of the far-right Alternative for Germany (AfD) are currently on a “fact-finding” trip to Syria, which the party wants classified as a safe-country of origin. This would make it easier to deport failed asylum seekers from Germany.
Syrians in Germany have been particularly angered by posts on the Facebook page of Christian Blex, a regional AfD lawmaker, who wrote that Syrian President Bashar Assad wanted the 600,000 Syrians who have sought refuge in Germany to return.
Chancellor Angela Merkel’s spokesman slammed the visit.
“Those who flatter this regime disqualify themselves,” Steffen Seibert told a regular news conference. “The Syrian regime shows every day how inhumanly it treats its own people.”
A spokesman for the AfD said the visit was private and did not represent the AfD’s parliamentary group in the Bundestag lower house, though it included some Bundestag deputies.