A deal has been reached to evacuate critically injured people from Douma, the last rebel-held town in Syria's Eastern Ghouta region, reports say.

The agreement follows negotiations between the rebel group Jaish al-Islam, civic leaders and Russia.

The wounded will be taken to Idlib, which is still in rebel hands.

Talks are continuing to spare Douma from a military offensive by the Syrian army and its allies, who currently surround it.

What do we know about the deal?

The rebels in Douma have denied they are negotiating an evacuation deal for the tens of thousands of civilians still living there.

However, the wounded will be allowed to leave under an agreement made with the Russian military late on Saturday, Reuters news agency says.

The rebels hope the talks will secure them the right to remain in Douma under Moscow's protection.

How many people have already left the Eastern Ghouta?

After six weeks of bombardment, thousands of rebels withdrew to the northern town of Idlib under a safe passage agreement.

The Syrian army has urged those still holding out in Douma to leave or face a full-scale offensive.

Tens of thousands of people have now left the suburbs east of Syria's capital, Damascus, which were once home to almost two million.

The Syrian army offers defeated rebels a choice between switching sides, or giving up their guns and relocating to government-controlled zones.

In a televised statement on Saturday, a military spokesman said the army had brought security to the capital, and safeguarded its links to the rest of the country.

How has the stand-off played out?

The Eastern Ghouta has been besieged by the Syrian government since 2013. UN Secretary General Antonio Guterres described conditions there as "hell on earth".

Residents suffered intense bombardment by Russian-backed Syrian government forces in recent weeks.

Food, fuel and medical stocks are low, and the relentless air strikes have driven many to seek shelter underground, where they are largely without sanitation.

The rebels have accused the government-backed forces of using napalm, chlorine and incendiary bombs against civilian areas.

UN war crimes experts are investigating several reports of rockets allegedly containing chlorine being fired this year.

The Ghouta assault has left more than 1,600 civilians dead and thousands more wounded, according to the UK-based Syrian Observatory for Human Rights.

Syria's military says it is trying to liberate the Eastern Ghouta from those it terms terrorists, and end their rocket attacks on the capital.

The rebels have fired their own shells at government-controlled areas of Damascus, causing dozens of casualties.

In January the Observatory said at least 60 people had been killed due to rebel bombardment since mid-November 2017.

Earlier in March Syrian state media said at least 35 civilians had been killed in a rocket attack on a busy market.