Turkish President Tayyip Erdogan said on Saturday that he had asked President Vladimir Putin for Russia to step aside in Syria and leave Turkey to deal with Syrian government forces alone, after 34 Turkish soldiers were killed this week.
Government forces, backed by Russian air power, have waged a major assault to capture the northwest province of Idlib, part of the last remaining territory held by rebels backed by Turkey.
Syrian and Russian warplanes on Saturday kept up air strikes on the Idlib city of Saraqeb, the Syrian Observatory war monitor reported. The strategic city sits on a key international roadway and has been a flashpoint of fighting in recent days.
Turkish strikes using drones and smart missiles late on Friday that hit Hezbollah headquarters near Saraqeb killed nine of its members and wounded 30 in one of the bloodiest attacks on the Iran-backed group in Syria, according to a commander in the regional alliance backing Damascus.
The Syrian Observatory said 48 pro-Damascus troops had been killed by Turkish strikes in the past 24 hours.
With diplomacy sponsored by Ankara and Moscow to ease tensions in tatters, Turkey has come closer than ever to confrontation with Russia on the battlefield.
Speaking in Istanbul, Erdogan said he had told Putin in a phone call to stand aside and let Turkey "do what is necessary" with the Syrian government. He said Turkey does not intend to leave Syria right now.
"We did not go there because we were invited by (Syrian President Bashar al-Assad). We went there because we were invited by the people of Syria. We don't intend to leave before the people of Syria say, 'Okay, this is done,'" Erdogan added.
As tensions rose, Russia and Turkey have held three rounds of talks, the first two of which did not yield a ceasefire.
Russia's Foreign Ministry said on Saturday that the two sides agreed in this week's talks to reduce tensions on the ground in Idlib while continuing military action there.
After 33 of its soldiers were killed on Thursday, Turkey said it would allow migrants it hosts to freely pass to Europe. One more Turkish soldier was killed on Friday, raising this month's toll to 55.
Turkey hosts some 3.7 million Syrian refugees, in addition to Afghans, Iranians, and Moroccans among others. It has warned that it cannot take another refugee wave from Idlib.
Violence in the northwestern Syrian province has displaced one million civilians since December inside the country near the Turkish border in desperate winter conditions, in what is perhaps the worst humanitarian crisis of the conflict.
Erdogan said that 18,000 migrants has crossed the border to Europe from Turkey since the gates were opened, without providing evidence, and added that the number could rise to 25,000-30,000 on Saturday.
Greece and Bulgaria, both European Union member states neighbouring Turkey, vowed not to admit the migrants. Greek police fired teargas toward migrants who were gathered on its border with Turkey and demanding entry on Saturday.
"We will not close these doors in the coming period and this will continue. Why? The European Union needs to keep its promises. We don't have to take care of this many refugees, to feed them," Erdogan said.
He said funds transferred to Turkey from the EU to support refugees were arriving too slowly and that he had asked German Chancellor Angela Merkel to send them directly to the Turkish government.
Turkey's borders to Europe were closed to migrants under an accord between Turkey and the EU that halted the 2015-16 migration crisis when more than a million people crossed into Europe by foot.
Bulgarian Prime Minister Boyko Borissov said he was planning to host a high-level meeting in Bulgaria to seek long-lasting solutions for Syria and migrants and would meet Erdogan on Monday to discuss it.
He said there was currently no migration pressure on the Balkan country's border with Turkey.
"We have to do everything possible next week, very quickly, until Wednesday, Thursday at the latest, to provide Turkey with the necessary means so that it can take the migrants back and take care of them," he told reporters.