In one of the heaviest clashes in northwestern Syria in a year, the army has retaken a key position and killed at least 22 militants in Hama province on Friday, a London-based observatory said Friday.

The clash erupted when the Syrian army seized a position held by the Jaish al-Izza militants near Halfaya village on the edge of the northwestern Idlib province, the so-called Syrian Observatory for Human Rights said.

At least 22 members of the militant group were killed in the clashes, and dozens more were wounded, the highest casualty toll of militants in the northwest in many months, it said.

According to the Observatory, government forces moved in to take a high building held by the rebels in a rural area of neighboring Hama province.

The Halfaya village, where the clashes broke out, is located in a planned buffer zone, which surrounds Idlib and also parts of the adjacent provinces of Aleppo and Hama.

Under a deal reached following a meeting between Turkish President Recep Tayyip Erdogan and his Russian counterpart Vladimir Putin in September, all militants must have withdrawn from the demilitarization zone by October 15.

However, the al-Qaeda-linked Takfiri terrorists said they refuse to either leave the buffer zone or hand over their weapons.

Moscow believed that the 15-20 kilometer buffer zone would help stop attacks from Idlib-based militants on Syrian army positions and Russia's military bases in the flashpoint region.

However, Russian Foreign Ministry spokesperson Maria Zakharova said Thursday that terrorists were continuing to make provocative acts in the demilitarized zone.

Zakharova said in her weekly press conference that in spite of the actual successes in establishing the demilitarized zone in Idlib and parts of Hama and Aleppo in accordance with the Turkey-Russia deal, it was premature to talk about completing this process.

She added that Nusra Front terrorists and their allies of other illegitimate armed groups were committing daily provocations there, the official Syrian Arab News Agency (SANA) reported.

Idlib and some surrounding areas are the last major bastions of Takfiri terrorists and anti-government militants in Syria, where the Syrian government has in recent months retaken much of the territory it had lost since the conflict erupted in the country in 2011.