DAMASCUS - Syria's foreign minister on Saturday linked any talks on the future of a rebel-held southern region with an end to US presence in another area bordering Iraq and Jordan.

Regime ally Russia has called for a meeting with the United States and Jordan on the future of the southern provinces of Daraa and Quneitra, bordering Jordan and the Israeli-occupied Golan Heights.

In recent weeks, Damascus has sent military reinforcements to the two provinces, which comprise some of the closest rebel-held areas to the capital.

President Vladimir Putin has spoken with Israeli Prime Minister Benyamin Netanyahu about proposed talks.

"We have not yet entered into negotiations over the southern front," Syria's Foreign Minister Walid Muallem said at a press conference in Damascus.

"The indicator will be the withdrawal of the United States from our land in al-Tanaf" near the Iraqi and Jordanian borders, Muallem said.

The United States and its allies have used a base in the area to train a force fighting the Islamic State militant group.

"Don't believe anything that is said about an agreement on the south until you see that the United States has withdrawn its forces from the At-Tanaf base," he said.

"It must withdraw its forces from At-Tanaf."

"We have strived from the start to resolve the issue in the ways that we are used to, which are reconciliations," he said. "If it is not feasible, we will see what will happen."

Moscow-brokered reconciliation deals have seen rebels withdraw from several areas of Syria including opposition strongholds close to the capital, often after blistering regime offensives and sieges. Last month, Washington warned Damascus it would take "firm" action if the regime violated a ceasefire deal for southern Syria that was negotiated with Russia and Jordan last year.

The warning came after regime aircraft dropped leaflets on Daraa, urging the rebels who control most of the province to lay down their weapons or face an offensive.

US-led coalition raids kill 12 civilians in Hasakeh

At least 12 civilians - members of the same family - have been killed in US-led coalition raids on the Islamic State group in northeastern Syria, a monitor said Saturday.

"The air strikes and artillery fire (Friday night) by the international coalition on the village of Hidaj, held by IS in the southern sector of Hasakeh province, killed at least 12 people," the Britain-based Syrian Observatory for Human Rights said.

The civilians - including two women and their children - belonged to the same family, it added.

The deaths bring to "20 the number of civilians killed by the coalition in 24 hours east of the Euphrates River", said the Observatory, which relies on a network of sources across Syria for its reports.

On Thursday, eight other civilians were killed in coalition strikes in Deir Ezzor province, south of Hasakeh.

IS militants have lost most of the self-proclaimed "caliphate" they once controlled in large parts of Syria and neighbouring Iraq since 2014.

Today, the militants hold less than three percent of Syria, according to the Observatory said.

In Deir Ezzor, the mainly Kurdish Syrian Democratic Forces - supported by the US-led coalition - are trying to dislodge militants from the east bank of the Euphrates.

The coalition said Friday its airstrikes in Syria and Iraq had "unintentionally" killed 892 civilians since its bombing campaign began nearly four years ago.

More than 350,000 people have been killed in Syria's war since it started in 2011 with a brutal crackdown on anti-government protests.

It has since spiralled into a complex conflict involving world powers and foreign militants.