Separately, the head of the United Nations humanitarian agency, Mark Lowcock, has warned that a ground offensive in Idlib could lead to the biggest loss of life this century has seen. "No matter what type of weapons or methods are used, the United States strongly opposes any escalation of violence in Idlib". "He's been warned. And so we'll see if he's wised up".
Iran shares the United Nations' concern about a potential humanitarian catastrophe in Syria's Idlib province and will seek to avert it, Hossein Jaberi Ansari, special assistant to Iran's foreign minister, told reporters on Tuesday.
In April 2017, Idlib was the site of a horrific chemical weapons attack that killed at least 74 people and injured more than 557.
Already hosting 3.5 million Syrians - the world's biggest refugee population - Turkey says it can not absorb more victims of the war and has accused the West of abandoning it to face the consequences of President Bashar al-Assad's reconquest of Syria.
That's right, unnamed U.S. officials are now claiming to be in possession of intelligence which they say shows Assad has already given the order in an absolutely unprecedented level of "pre-crime" telegraphing of events on the battlefield.
"All members of the global community must understand their responsibilities as the assault on Idlib looms".
Idlib's main towns and cities are under the sway of jihadists linked to al Qaeda's former Syrian affiliate, the Nusra Front, though they are outnumbered by Turkey-backed FSA fighters grouped under "The National Front for Liberation".
Erdogan has called for a cease-fire in the northwestern province of Idlib, the last opposition stronghold in Syria, as an assault by Syrian regime forces is expected any day.
During his remarks, Russian Ambassador Vassily Nebenzia repeated the claim that "Syria has no chemical weapons", and said it would be folly on a humanitarian and political basis for the Assad regime to use chemical weapons, as it would prompt the USA and others to attack inside Syria.
Erdogan on Monday said in the Wall Street Journal: "All members of the global community must understand their responsibilities as the assault on Idlib looms".
Haley warned of dire consequences if mass casualties were caused if the assault went ahead.
Russian Federation responded and insisted that the planned assault on Idlib is a "counterterrorism operation" and that measures will be taken to spare civilians.
"The Turks are making sure they have enough munitions that keep them going for a long while", he added.
"The Turkish border is sealed, the Turks have kept that border quite tightly shut for the past few years, so al-Assad's opponents don't have anywhere to run to", she said.
About 3 million people live in the opposition-held area, which comprises most of Idlib province and adjacent small parts of Latakia, Hama and Aleppo provinces.
Regime leader Bashar al Assad has now set his sights on Idlib, and his forces have stepped up bombardment of the densely populated province since the beginning of the month. "That's something we're monitoring very closely", OCHA spokesman David Swanson said.
But he stressed that "there are 100 civilians, majority women and children, for every fighter in Idlib".
The security source said Turkey was preparing more camps, but said discussions were still continuing about the scale of the aid operation inside Syria.