Sweden's UN Ambassador Olof Skoog said "the de-escalation agreement is meant to help and support the UN-led political process in Geneva, which for us is key". "Who is going to be ensuring they're safe?"
"I don't exclude the possibility of violating the memorandum of the de-escalation areas by Turkey which is one of the guarantor states who signed the memorandum", said Moallem, who is also Foreign and Expatriates Minister.
"What they say is that we now sit down and agree, they will agree with our input on whom should be controlling security (and) the monitoring", he said.
"We'll look at the proposal, see if it can work", said Mattis, who will attend a meeting of the anti-IS coalition in the Danish capital.
The memorandum signed by Russia, Turkey and Iran came into effect on the weekend and calls for a truce - renewable after six months - between government and opposition forces in four designated safe zones as well as the delivery of aid and medical supplies.
The United States is not party to the de-escalation agreement, and the Syrian government and opposition have not signed on to the deal.More news: House Democrats Demand White House Turn Over Any Comey Recordings
Lavrentyev, whose remarks were carried by Russian news agencies, said "the operation of aviation in the de-escalation zones, especially of the forces of the global coalition, is absolutely not envisaged, either with notification or without".
"We have not changed or altered our operations in any way", Davis said.
There has been, he said, "a strong acknowledgement from Putin that the United States and UN have a role to play, and that's what I hope to see next, as without them I don't see much progression".
"Will it affect the fight against the ISIS [Daesh]? I think the global community is united in the sense of wanting to see ISIS put on its back foot", the defense secretary said.
Mattis, in some of the most extensive remarks by the Trump administration so far, was cautious when asked about the deal's chances as he traveled to Copenhagen for talks with US allies.
Both diplomats will still travel to Fairbanks for that summit, where Tillerson will also meet individually with other foreign ministers.More news: My name is being used for political gains: Rajinikanth
More than 320,000 people have been killed in Syria since the conflict began with demonstrations against Assad.
The Russian statements could also signal an effort to limit USA strikes against Syrian regime forces like the one carried out in retaliation for a chemical attack last month.
Syria's foreign minister said on Monday that his government would abide by the terms of a Russian plan for "de-escalation" zones so long as rebels also observed it.
"This subject was brought up, but there's a lot of details to be worked out", Mattis said.
For the first time, with the participation of the guarantor countries, a mechanism was developed to stop the civil war in extensive areas of the Syrian territory, the director of the National Defense daily, Igor Korochenko, stated.
Speaking about the military situation inside Syria, Moualem said Deir al-Zor, a city and province occupied by Islamic State in the east, was the "fundamental objective" for government forces and more important to the average Syrian than Idlib.More news: Melissa McCarthy adds spice (and Spicer) as host of 'SNL'
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