Air strikes killed 10 civilians including seven children in areas near a town held by the Islamic State group in north Syria on Saturday, a monitor said.

The strikes came as regime forces had advanced to within seven kilometres (four miles) of the jihadist group's bastion of Al-Bab, the Syrian Observatory for Human Rights said.

The Observatory said regime airstrikes killed a child in Tadif on Saturday, while Turkish air raids left nine civilians dead including six children in Al-Uraima and Bezaa.

President Bashar al-Assad's fighters have advanced towards Al-Bab from the southwest, seizing three villages since late Friday, the Observatory said.

Turkish forces, meanwhile, have gathered to the north of the town, the Britain-based monitor said.

Al-Bab has come under heavy assault in recent weeks, with Turkish, Russian and Syrian warplanes carrying out strikes in or around the town.

Turkish forces regularly carry out air strikes in support of a ground operation they launched in Syria last August targeting both IS and Kurdish fighters.

Several this month have been joint operations with Russia.

Turkish officials say the utmost is done to avoid causing civilian casualties, and have denied claims that civilians have been killed in previous raids.

The Observatory has also reported that 10 civilians were killed on Friday in Turkish air strikes and shelling in the area.

Turkey's state-run Anadolu news agency reported on Friday that the latest round of raids had killed 22 IS "terrorists".

IS is not included in a fragile nationwide ceasefire in force since December 30 that led to peace talks jointly organised by Turkey, Russia and Iran in Kazakhstan this week.

Ankara has backed rebels since the conflict began with the brutal repression of anti-government protests in March 2011.

Moscow and Tehran have supported the government.

The Observatory, which relies on a wide network of sources inside Syria for its information, says it determines whose planes carry out raids according to type, location, flight patterns and munitions used.

France has dropped twice as many bombs on IS as in Libya: airforce chief
On An Airbase In Jordan, Jordan (AFP) Jan 30, 2017 - French warplanes have used twice as much firepower against the Islamic State (IS) in Syria and Iraq as in the campaign to oust Libyan dictator Moamer Kadhafi in 2011, according to Air Force Chief of Staff Andre Lanata.

In an interview with AFP, Lanata said Mirage jets taking off from bases in Jordan and United Arab Emirates had dropped 1,800 bombs since France joined the US-led anti-IS coalition in 2014.

The total figure, including strikes carried out by planes taking off from the Charles de Gaulle aircraft carrier, stood at 2,300, he said.

"That's twice as many as in Libya in 2011 and four times more than in the Serval and Barkhane operations (against jihadist groups in the Sahel)", Lanata said during a weekend visit to a base used by French forces in Jordan.

France, which has been targeted by a wave of jihadist attacks, ratcheted up its strikes against IS after the Paris massacre of November 2015 which was claimed by the group.

The coalition is currently focusing its strikes on the Iraqi city of Mosul -- which is being fought over by Iraqi forces and IS -- as well as the jihadists' Syrian stronghold of Raqa.

Lanata said the air campaign -- the bulk of which is being shouldered by the US, with France and Britain playing the main support roles -- was straining resources.

"I'm having a hard time (recruiting and retaining personnel) in a number of positions, from plane mechanics to intelligence officers, image analysts and base defenders."

"We also have historical capacity shortcomings," he said, pointing to aerial refuelling tankers "that are on average 55 years old" as well as a shortage of drones and other surveillance devices.