Syrian government forces have continued to tighten their grip around Aleppo province, as they push for the Islamic State of Iraq and the Levant's (ISIL) stronghold in Raqqa, a monitoring group and state media have said.

The UK-based Syrian Observatory for Human Rights said on Sunday that government forces backed by Russian air strikes have captured 18 villages in Aleppo's eastern suburbs - giving them access to 40km of the highway between Aleppo and Raqqa.

The stretch of highway passes by the Kweires military airport that government forces recaptured in November.

The latest government advance in Aleppo comes after days of deadly clashes against ISIL fighters who control parts of northern Syria, including Raqqa province. 

Syrian state news SANA said on Saturday evening that the Syrian army "restored security and stability to a number of villages" in Aleppo's northeastern suburbs.

"Full control was established over the Thermal Power Station and a number of surrounding villages in the eastern countryside of Aleppo.

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"Army units defeated the remaining remnants of ISIL terrorist organisation from the Thermal Power Station and the surrounding areas 30km to the east of Aleppo," SANA reported on their website.

The Syrian government launched a major offensive from the north of Aleppo and captured several strategically important towns earlier this month.

The offensive has led to the displacement of more than 50,000 civilians from Aleppo, tens of thousands of whom have amassed in camps at the Turkish border.

ISIL loses ground

Meanwhile in the southern suburbs of Hasakah province, the Syrian Democratic Forces clashed with ISIL fighters on Saturday evening.

The Observatory said the SDF have captured several villages around ISIL-controlled Shadadi city in Hasakah province. The group launched an offensive against ISIL last week and said they cut several supply lines for the group in the area.

The SDF was founded in Syria's mainly Kurdish northeastern region in October 2015, and is made up of at least 15 armed factions - mostly fighters from the YPG and the Free Syrian Army

Ceasefire talks

On Saturday, a number of Syrian opposition groups declared that they agree to the "possibility" of a temporary truce if President Bashar al-Assad's government and its allies respect several conditions, including halting fire.

The groups said they would agree provided there were guarantees that the Syrian government forces and its allies would respect a ceasefire, sieges were lifted and aid deliveries permitted across the country.

Assad said in an interview with Spanish newspaper El Pais on Saturday that he was ready to implement a long-sought ceasefire, but only if the rebels and their international backers such as Turkey did not use it as a chance to gain ground.

Separately, the Observatory also released a report on Saturday saying that at least 7,842 civilians have been killed in Syrian and Russian air strikes across the country.

The death toll includes 1,668 children below the age of 18. The air strikes have also left at least 40,000 civilians injured, the Observatory said.

"Since November 2014, the Syrian government conducted at least 49,307 air strikes. Included in that figure , the government has dropped at least 27,735 barrel bombs," the report said.

Courtesy Aljazeera