Changes are afoot in the situation in Syria as government forces make gains in the Aleppo region, which leads to the belief that Turkey's attempts to maintain troops in the country is being countered.

Syrian troops made significant advances on Sunday against the last rebel held enclaves in the country's northwest, consolidating the government's hold over the key Aleppo Province, according to the official Syrian Arab News Agency.

The Syrian government advance also appeared to put the provincial capital of Aleppo out of the firing range of opposition groups for the first time in years, another sign of Syrian President Bashar al-Assad's growing control of the area.

The Syrian government is increasingly unable to tolerate the long-standing existence of Turkey-backed opposition forces in Idlib, said Zou Zhiqiang, a researcher at Shanghai International Studies University's Middle East Studies Institute.

"Also, the presence of the Turkish army, and even the continued increase in troops and free movement, within Syrian territory has also provoked the Syrian government's strong dissatisfaction," he said.

The key point of Syria's future situation lies in the presence of the Turkish army on the ground, Zou said.

He said establishing a demilitarized zone in the west of Aleppo was more like "a transitional measure "that the Syrian government is not satisfied with.

The zone in Syria's Idlib Province was created in 2018 under an agreement between Turkey and Russia to be patrolled by military forces from the two countries.

"In the short term, Russia-Turkish relations will become more tense, and new military frictions may also erupt again, which will have an impact on the Astana process and the Russian-Turkish-Iranian trilateral cooperation mechanism," Zou said. Both Iran and Russia back the Syrian government in the civil war.

Meanwhile, the state-run Al-Ikhbariya TV said that government troops were still besieging remnants of opposition fighters in a small part of rural western Aleppo.

Also, parts of northern Aleppo region, which straddles the border with Turkey, is administered by Turkey and allied Syrian factions. And another segment of the province further west is controlled by Kurdish-led forces, allied with the United States. Both parts have not been part of the government offensive.

The armed opposition is now squeezed into a shrinking area of nearby Idlib province, where the government is also on the offensive.

Separately, Assad on Sunday highlighted his administration's determination to retake all Syrian areas from the rebels.

"The Syrian people are determined to liberate all Syrian territories," said the president.

Agencies and Xinhua contributed to this story.