US, UK, France and Germany urge political solution to Syria conflict

Aleppo now under rebel control after lightning offensive

Anti-government fighters reach the motorway near the northern Syrian town of Azaz. AFP

Anti-government fighters celebrate as they take over the northern Syrian town of Tal Rifaat. AFP

Anti-government fighters swept into the city of Aleppo, east of Idlib province. AFP

The Syrian army said dozens of its soldiers had been killed in the attack on Aleppo. AFP

Smoke billows in the aftermath of what the White Helmets say is a strike, in Idlib, Syria. Reuters

Syria's President Bashar Al Assad meets Iran's Foreign Minister Abbas Araghchi, in Damascus. Reuters

A nurse attends to an injured woman in Idlib, Syria. Government air strikes in Idlib killed at least three civilians, including two children, and wounded 11 others, said the Syrian Civil Defence. AP

Anti-government fighters take a position near the northern Syrian town of Tal Rifaat. AFP

Anti-government fighters ride a motorcycle in the northern Syrian town of Tal Rifaat. AFP

People cross an anti-government checkpoint as they return to the town of Saraqib in the eastern part of Idlib province. AFP

Syrian opposition fighters seize abandoned Syrian army ammunition in the town of Khan Assubul, Syria, southwest of Aleppo. AP

The governments of the US, UK, France and Germany on Sunday said they are closely monitoring developments in Syria and called for de-escalation and a political solution after a shock rebel offensive reignited the country's civil war.

The statement from the four western nations came as US Secretary of State Antony Blinken and Turkish Foreign Minister Hakan Fidan spoke about the “rapidly developing” conflict in Syria.

Rebel troops last week seized control of the second-largest city Aleppo in a lightning offensive that so far has killed more than 400 people, most of them fighters, according to a Syrian war monitor.

We urge “de-escalation by all parties and the protection of civilians and infrastructure to prevent further displacement and disruption of humanitarian access,” the four countries' statement read. “The current escalation only underscores the urgent need for a Syrian-led political solution to the conflict”.

Similarly, Mr Blinken and Mr Fidan discussed “the need for de-escalation and the protection of civilian lives and infrastructure in Aleppo and elsewhere,” State Department spokesman Matthew Miller said.

The call came after Syrian rebels and their Turkish-backed allies launched their biggest offensive in years, seizing Aleppo from troops loyal to President Bashar Al Assad.

The flare-up has also seen pro-Turkish rebel groups attacking government troops and Kurdish People's Defence Units (YPG) fighters in and around Aleppo, a Syrian war monitor said.

Turkey sees the YPG as an offshoot of the banned Kurdistan Workers' Party (PKK), which has led a decades-long insurgency against Ankara.

Another complicating factor in the new fighting is the presence of about 900 US troops who are in northern Syria to fight ISIS alongside local partners.