Britain is debating whether to join the US and France in carrying out air strikes on Islamic State (Isis) targets in Syria. Russia says it has agreed with France that its air strikes will also target only IS. The West had accused Moscow of mostly targeting Western-backed rebel groups fighting Syrian President Bashar al-Assad.

On 29 November, air strikes believed to have been carried out by Russian jets killed at least 30 people at a busy marketplace in the town of Ariha in north-western Syria. Rebel-held areas in the north west near the Turkish frontier reported intensified air strikes in the days after Turkey downed a Russian warplane.

Syria air strikes
People mourn over bodies of people who died during what activists said were air strikes carried out by the Russian air force on a busy market place in the town of Ariha, on 29 November 2015Ammar Abdullah/Reuters
Syria air strikes
Produce at a market is covered in dust as people inspect a site hit by what activists said were air strikes carried out by the Russian air force in the town of Ariha, in Idlib province, on 29 November 2015.Ammar Abdullah/Reuters

On 26 November, an air strike on a water treatment plant in Syria cut water supplies for 3.5 million people. Syrian state news agency SANA reported that the US-led coalition had bombed the water plant, while the Syrian Network for Human Rights blamed Syrian government warplanes. Neither gave any evidence for their assertions.

Syria air strikes
Residents inspect a site that contained a drinking water well, damaged by an air strike in the rebel-controlled area of Al Ghariya village, in the eastern Syrian countryside of Deraa, on 12 November 2015Alaa Al-Faqir /Reuters

On 28 November, medical charity Medecins Sans Frontieres (MSF) said seven people died and 47 were wounded after helicopters dropped four barrel bombs on the rebel-held town of Al Zafarana, north east of the city of Homs. The first bomb struck a populated area of the town and the next three landed next to the MSF-supported hospital where the casualties were taken, partially destroying the complex. Assad has denied his forces use barrel bombs. Their use has been widely documented by monitors of the Syrian conflict.

Prior to the agreement to target only IS territory, Russian air strikes in north-west Syria had heavily targeted ethnic Turkmen areas, according to Russian Defence Ministry data analysed by Reuters. This helps explain rising tensions between Moscow and Ankara in the weeks before Turkey shot down a Russian warplane. Russian missiles destroyed ammunition bunkers, command points and a suicide bomb factory in towns including Salma, which is used as a base by Turkish-backed rebels in their fight against Assad.

Syria air strikes
A building hit by what local residents said were air strikes carried out by the Russian air force on a Turkish grain mill factory is seen in the town of Saraqib, in Idlib province, on 1 December 2015Ammar Abdullah/Reuters
Syria air strikes
Damaged trucks are seen after what activists said were air strikes carried out by the Russian air force, on a parking garage for cargo trucks in al-Dana town, near the Syrian-Turkish border on 28 November 2015Ammar Abdullah/Reuters
Syria air strikes
Residents inspect a damaged site from what activists said were air strikes carried out by the Russian air force in Nawa city, Deraa, on 21 November 2015Alaa Al-Faqir/Reuters
Syria air strikes
Residents toss belongings from a damaged building from what activists said were air strikes carried out by the Russian air force in Nawa city, Deraa, on 21 November 2015Alaa Al-Faqir/Reuters
Syria air strikes
A still image taken from video footage, released by Russia's Defence Ministry on 20 November 2015, shows a ground crew member writing the words "For Paris" on a bomb on a Russian military jet at the Hmeymim air base near LatakiaMinistry of Defence of the Russian Federation/Reuters
Syria air strikes
Residents inspect a site hit by what residents said were air strikes carried out by the Russian air force in the town of Darat Izza in Aleppo province, on 13 October 2015Ammar Abdullah/Reuters
Syria air strikes
Russian Tupolev TU-22 long-range strategic bombers conduct an air strike at an unknown location in Syria, in this still image taken from video footage released by Russia's Defence Ministry on 18 November 2015Ministry of Defence of the Russian Federation/Reuters
Syria air strikes
Men ride a motorcycle at a site hit by what activists said were air strikes carried out by the Russian air force in the rebel-controlled area of Maaret al-Numan town in Idlib province, on 24 October 2015Khalil Ashawi/Reuters
Syria air strikes
A man runs through dust at a site hit by what activists said were air strikes carried out by the Russian air force in the rebel-controlled area of Maaret al-Numan town in Idlib province, on 24 October 2015Khalil Ashawi/Reuters
Syria air strikes
Civil defence members and civilians search for survivors under the rubble of a site hit by what activists said were cluster bombs dropped by the Russian air force in Maasran town, south of Idlib province, on 7 October 2015Khalil Ashawi/Reuters
Syria air strikes
Unexploded cluster bomblets are seen inside the remains of a cluster munition that activists say was fired by the Russian air force on Maasran town, in the south of Idlib province, on 7 October 2015Khalil Ashawi/Reuters
Syria air strikes
Men look at a crater caused by what activists said was a Russian air strike in Latamneh, in the northern province of Hama, on 2 October 2015Ammar Abdullah/Reuters
Syria air strikes
A civil defence member tries to extinguish a military vehicle at a base in the south of Idlib province controlled by rebel fighters from the Ahrar al-Sham Movement, targeted by what activists said were Russian airstrikes, on 1 October 2015Khalil Ashawi/Reuters
Syria air strikes
Rebel fighters drive a vehicle past by a building that activist said was hit by Russian air strikes in Latamneh, northern Hama province, on 2 October 2015Ammar Abdullah/Reuters
Syria air strikes
People inspect a site hit by what residents said were air strikes carried out by the Russian air force in the town of Darat Izza in the province of Aleppo, on 7 October 2015Ammar Abdullah/Reuters
Syria air strikes
Russian President Vladimir Putin shakes hands with Syrian President Bashar al-Assad during a meeting at the Kremlin in Moscow on 20 October 2015. Assad made a surprise visit to Moscow to thank Putin for launching air strikesAlexei Druzhinin/RIA Novosti/Kremlin/Reuters

Prime Minister David Cameron has said he believes British warplanes, which have been bombing IS targets in Iraq for more than a year, should also be tackling the group in Syria rather than "sub-contract" national security to other countries.

But Labour leader Jeremy Corbyn says strikes would be ineffective and kill civilians. He has accused Cameron of an ill-thought-out rush to war: "The prime minister has been unable to explain why extending air strikes to Syria – which is already being bombed by the US, France, Russia and other powers – will make a significant military impact," Corbyn wrote in the Guardian. The 66-year-old has repeatedly cited Britain's deeply unpopular role in the US-led invasion of Iraq in 2003 as cause for caution. Former prime minister Tony Blair acknowledged in October the Iraq war had played a part in the rise of IS.

A YouGov opinion poll showed voter support for military action in Syria had fallen to the lowest level since September 2014. Syria's conflict has killed more than 250,000 people and wounded more than a million since the start of an uprising against Assad in 2011.

Syria air strikes
A Royal Air Force Tornado takes off from RAF Lossiemouth in Scotland, on 2 December 2015Russell Cheyne/Reuters