The Turkish intelligence apparatus continue to exert efforts to persuade extremist groups out of Syria's demilitarized zone, as the extremists have rejected to leave according to a Russian-Turkish plan, a war monitor reported on Tuesday.

The Syrian Observatory for Human Rights said the Turkish intelligence is continuing its "undeclared" efforts to push the ultra-radical groups out of the demilitarized zone in northern Syria, which should have been done by Oct. 15.

It said calm prevailed the demilitarized zone on the second day of its supposed implementation.

The Britain-based watchdog group said the Russian-Turkish deal to impose a buffer zone between the Syrian army and the rebel groups in northern Syria has been partially implemented in terms of pulling out heavy weapons from the zone.

However, the second stage of the deal is for the ultra-radical rebel groups to withdraw, which did not happen as such groups, mainly al-Qaida-linked groups, have rejected to pull out.

The planned demilitarized zone stretches from the northeastern countryside of Latakia province to the northern countryside of the province of Hama and western countryside of Latakia as well as areas in the countryside of Idlib province in northwestern Syria.

The Hayat Tahrir al-Sham, otherwise known as al-Qaida-linked Nusra Front, is considered as the most powerful among the rebel groups in Idlib province, the last major rebel stronghold in Syria.

The deal for imposing a demilitarized zone was reached in September between the leaders of Turkey and Russia, aiming at averting Idlib province from a wide-scale offensive by the Syrian army.

The Syrian government has welcomed the deal but noted that it was only temporary.

Turkey's task in the deal is to persuade the rebel groups in Idlib to abide by the plan as Ankara enjoys sway over the militants there.

The Observatory said that no Turkish-Russian patrols have yet started in the demilitarized zone as planned.

A day earlier, Syria's Foreign Minister Walid al-Muallem said that there should be more time to judge the success or failure of the deal, and that the Syrian army is standing by around Idlib should the rebels fail to abide by the plan.

The Syrian government officials repeatedly said that the demilitarized zone should end after Idlib and the surrounding rebel-held areas return under the government control.

In his remarks on Monday, al-Muallem was confident that Idlib will return under the government control, adding that the next goal of the Syrian government is to restore areas on the eastern bank of the Euphrates River, which is under the sway of the U.S.-backed Kurdish-led Syrian Democratic Forces (SDF).

Throughout the crisis, Idlib has emerged as the major destination and stronghold of the Syrian rebels fleeing other parts of the country after deals or surrender.

Idlib is now in a state of severe lawlessness characterized by assassinations, explosions and infighting.

The major rebel group in Idlib is the Nusra Front and its umbrella of the Hayat Tahrir al-Sham.

The group has vowed not to surrender, saying it will keep on fighting the Syrian army.

Idlib is of strategic significance as it shares a border area with Turkey in the north, and neighbors the coastal province of Latakia, hometown of Syrian President Bashar al-Assad.

Notably, the namesake capital city of Idlib lies close to the international road linking the capital Damascus with the northern province of Aleppo.

Idlib is home to around 3.5 million people, including those evacuated after the surrender of rebels in other Syrian areas.

Muallem said in his Monday remarks that the government prioritized resolving the situation in Idlib through reconciliation to spare the lives of people in Idlib.

However, the minister noted that the Syrian army cannot stand indifferent about the situation in Idlib if it wasn't resolved as up to 50,000 rebels are believed to be positioned there.