UNITED NATIONS (AP) — Secretary-General Antonio Guterres again called for an immediate cease-fire in northwestern Syria Friday “before the situation gets entirely out of control,” and 13 of the 15 nations on the U.N. Security Council supported his appeal at an emergency meeting — but not Syria’s closest ally Russia and China.

The U.N. chief made the appeal after airstrikes in the last opposition stronghold in Idlib killed at least 33 Turkish troops on Thursday. The attack heightened tensions between pro-opposition Turkey and Russia, and raised the possibility of an all-out war with millions of Syrian civilians trapped in the middle.

Guterres said he’s been in very close contact with Russia and Turkey, appealing for a cease-fire in the Idlib region but “we are not yet there.”

“Without urgent action,” he warned, “the risk of even greater escalation grows by the hour.”

The four European Union council members — France, Germany, Belgium and Estonia — said in a joint statement that “the military escalation in Idlib must stop.”

“We demand an end to this Syrian military campaign supported by Russia, and fully back the calls made by the U.N. secretary-general for an immediate cease-fire and unimpeded humanitarian access,” they said. “We strongly urge the U.N. to accelerate and intensify their engagements with all relevant parties to secure an immediate cease-fire effort in northwest Syria.”

The four EU countries requested the emergency meeting along with the United Kingdom, United States and Dominican Republic.

U.S. Ambassador Kelly Craft condemned the attacks on the Turkish troops “in the strongest possible terms,” calling them “wholly unjustified, senseless and barbaric.” She reiterated U.S. calls for “an immediate, durable, and verifiable cease-fire”

Craft said the council meeting is “about the reckless and serious risk of the Assad regime and Russia’s offensive places on the security of a NATO ally,” but it is also about the 950,000 Syrians who have fled the government’s offensive that began in December, many now living in flimsy tents and in the open in freezing temperatures.

She asked again: “Are we going to sit back and watch? Are we going to remain silent? Or will we deliver? How many more babies have to freeze to death before we raise our voices and say, `Enough!’”

Estonia’s U.N. Ambassador Sven Jurgenson said Russia has blocked Security Council resolutions calling for a nationwide cease-fire.

“In light of what has happened, we urge Russia to reconsider its position and allow a chance for a humanitarian truce,” he said.

But Russia’s U.N. Ambassador Vassily Nebenzia said over recent months, “terrorists” seized Idlib and the Jihadi group Hayat Tahrir al-Sham or HTS, “has upped its incursions” against civilians and Syrian forces.

“The Syrian army is fully in its right to respond and clamp down on the terrorists,” he said. “This is in its own territory.”

China’s U.N. Ambassador Zhang Jun said “terrorism is an underlying factor” in the nine-year Syrian conflict and “eradicating the forces of terror is a necessary requirement for the restoration of peace and stability in Syria and the region.”

Terrorists “should be resolutely crushed, and safe havens established by terrorist forces in Syria should be liquidated,” he said. “At the same time, counter-terrorism operations should be cautious not to harm civilians.”