MOSCOW -- Russia has grounded its warplanes in Syria to help secure a ceasefire brokered by Moscow and Washington that entered into force Saturday, a top military official said.

Lt.-Gen. Sergei Rudskoi of the General Staff of Russia's military said that while Russia will continue air strikes against the Islamic State group and al Qaeda's branch in Syria, Jabhat al-Nusra, it is keeping its aircraft on the ground for now "to avoid any possible mistakes."

Rudskoi said that 17 opposition units have contacted the Russian military to adhere to the truce that became effective at midnight local time.

He said the Russian military had established hotlines to exchange information with the U.S. military in order to help monitor the ceasefire and quickly respond to any conflict situations.

Rudskoi said that Russia has given the U.S. maps showing the location of opposition groups pledging to abide by the ceasefire as well as IS and al-Nusra units. He said 74 opposition units including more than 6,100 fighters have agreed to adhere to the truce.

The U.S., in its turn, also has provided the Russian Defence Ministry with similar maps and its own list of opposition units, which have agreed to respect the ceasefire.

Rudskoi said that a rebel unit that accidentally comes under attack should contact Russian or U.S. representatives who would quickly "take measures to end the violation and quickly de-escalate tensions."

"Russia is fully observing its obligations under the ceasefire," he said. "But it doesn't mean that the IS and Jabha al-Nusra militants can breathe a sigh of relief. The fight against bandit groups considered terrorist by the United Nations will continue."

He said that Russia is using 70 drones along with satellites and other intelligence means to monitor the situation in Syria.

The Russian co-ordinationcentre at the Hemeimeem air base in Syria's coastal province of Latakia where Russian warplanes are based has 61 officers, who negotiate with groups willing to join the cease-fire and co-ordinate the deliveries of humanitarian aid.

The centre chief, Lt.-Gen. Sergei Kuralenko, who spoke via a video link from the base, said fighting has stopped in 34 towns and villages in the provinces of Hama, Homs, Damascus. He added that his officers are currently preparing ceasefire documents for another 47 towns.