Forces loyal to Syria’s Bashar Al Assad regime have launched a major offensive to retake a besieged opposition enclave in the southern province of Daraa, opposition sources said. Shelling and rocket fire by Mr Al Assad’s army and Shiite militia supported by Iran killed at least two people in the district of Daraa Al Balad on Sunday, the sources said. Heavy clashes were reported in the area. For almost a month, rebels had resisted a deal supervised by Russia, an ally of Damascus, to leave in return for the district not being overrun by the regime. “After three days of shelling, the regime is raising the pressure by trying to advance on the ground,” a Syrian opposition figure in Amman said on condition of anonymity. The regime and its allies have a huge firepower advantage, but it appears they lacked approval from Russia to launch a full-blown assault to take Daraa Al Balad after a month-long siege. It is not clear whether the attack is a final assault on the enclave, in which thousands of civilians live. The Russian military has not provided air cover for the latest regime offensive, a departure from its approach in other rebel areas besieged in the war. Daraa is a rare example of Russia’s intervention in the Syrian civil war being tempered by the need to maintain relations with other countries, and other calculations Moscow considers to be strategic. Several diplomats in the Middle East and opposition figures in Amman say Daraa’s proximity to Jordan and Israel were a factor in Moscow preferring a settlement. Russia’s wish to project an image of itself as a peacemaker and to draw international reconstruction funds to Syria led it to treat Daraa differently, they said. In 2018, Moscow supervised a tacit deal between Russia, the US and Israel for the province to come under regime control once more. But the local population has not been expelled and the regime did not restore full control, as has happened in other Russia-designated “de-escalation” zones in Syria. The three-year Russian-imposed peace in Daraa has been marred by numerous assassinations of regime and rebel figures. It collapsed late last month after the rebels of Daraa Al Balad, a district in the province, and in opposition towns in the countryside launched a pre-emptive attack on regime and pro-Iranian militia positions. They said the attack in late July aimed to prevent what they described as an impending regime takeover of the district. For almost a month, most of the 400 or so rebels in Daraa Al Balad have rejected Russian pressure to accept expulsion of one-fourth of their number to areas of Turkish influence in northern Syria. Under the Russian-proposed deal, the rest of the rebels would have to hand over their weapons and accept a resumption of regime control. About 50 fighters and civilians left in green buses last week as the deal swung between partial implementation and rejection by the rebels. Daraa is in the Hauran Plain, birthplace of the 2011 revolt against five decades of Assad family rule. Russian intervention in late 2015 tilted the post-revolt civil war in favour of the regime. A committee representing towns in Hauran that are still with the opposition said on Monday that “regime forces insist on dragging the region into a fierce war”.