The agreement on safe zones in Syria will come into force from midnight on Friday, but Russia's air force will continue striking Islamic State elsewhere in the country, Russian news agencies cited Russian Defence Ministry as saying on Friday.

The first and the largest safe zone in northern Syria will include the Idlib province and adjoining districts of Latakia, Aleppo and Hama with a total population of over 1 million, the Ministry said.

The position of the United States allowed to create conditions for political settlement in Syria, the agencies quoted Russian Deputy Defence Minister Alexander Fomin as saying.

The fact that the de-escalation agreement was supported by the United Nations, the United States and Saudi Arabia guarantees its implementation, he said.