BEIRUT — Syrian government forces have surrounded rebel-held parts of the city of Daraa as part of their offensive in the southwestern province, activists said Monday.

The city was where the uprising against President Bashar Assad began seven years ago as part of the Arab Spring wave of protests before Syria descended into a full-blown civil war that has claimed the lives of some 400,000 people and displaced more than 5 million as refugees.

Rebel strongholds in southern Syria have been crumbling since the government launched a ground offensive on the area last month, under the cover of Russian airstrikes. Last week, Russia brokered a deal with the rebels under which they are to hand over their heavy weapons and a main border crossing point with Jordan. Rebels who rejected the deal are to be evacuated to the country's north.

The Britain-based Syrian Observatory for Human Rights and rebel spokesman Ibrahmi Jabawi said the siege of the rebel-held parts of the city of Daraa, the capital of the province with the same name, started on Sunday night.

The Observatory and the government-controlled Syrian Central Military Media said troops now also control most areas along the Jordanian border, after taking the main border crossing there.

The Observatory also said that after taking the villages of Heet and Zeizoun in the province, government forces have reached the area controlled by the Khaled bin Al-Waleed Army, which is linked with the Islamic State group.

State news agency SANA said military experts are dismantling explosives in the area.