Syrian opposition groups are resisting Jordanian pressure to hand control of a border crossing back to the Syrian government, a step that would be a major boost for President Bashar al-Assad and undermine rebel groups in southwestern Syria, reported Reuters. 

Talks over reopening the Nasib crossing have gathered pace since a Russian-U.S. brokered ceasefire in July brought relative calm to southern Syria, the first peacekeeping effort in the war by U.S. President Donald Trump’s administration.

But rebel groups which seized control of the crossing in 2015 have so far resisted proposals for a return of Syrian government authority to Nasib, even in the form of civilian officials with no Syrian army presence.

The possibility of the crossing being reopened underlines just how far the scales have tipped in favor of Assad, who is steadily winning back territory with Russian and Iranian help, forcing neighboring states to rethink their policies.

“The presence of any regime employee is like restoring legitimacy to a worn-out regime against which the Syrian people rose up,” said Adham al Karad, a Free Syrian Army (FSA) rebel commander who led battles in Deraa city against the army.

Jordan has trodden a careful path during the six-year long war, maintaining diplomatic ties with Damascus even as it became a hub for a U.S.-led program that funneled aid to vetted Syrian rebels. Trump recently decided to shut down that program.

Jordan has put forward proposals by which rebels would secure the road to Nasib, 100 km (60 miles) from the capital, while a civil administration from Damascus would run the crossing, according to Syrian opposition officials. Rebels would receive a portion of the customs fees as part of the deal.

The proposals were discussed during a meeting between the Jordanian government and opposition-run local councils and rebels from southern Syria in Amman at the end of last month.