France said on Tuesday it had unlocked an extra 50 million euros for humanitarian aid to Syria, half of which will be destined for the Idlib region. France will carefully monitor whether this aid "effectively reaches civilians," the presidential palace said in a statement following a videoconference between French President Emmanuel Macron and the leaders of Germany, Turkey and Britain. Discussions focused on the Syria crisis and migrant issue as well as joint action against coronavirus, Turkish presidency said. In a statement, the presidency said Turkish President Recep Tayyip Erdogan, French President Emmanuel Macron, German Chancellor Angela Merkel and British Prime Minister Boris Johnson also discussed methods of humanitarian aid to Syrias northwestern Idlib province. The call was planned after Ankara opened its borders to migrants trying to enter the bloc. Separately, US Secretary of State Mike Pompeo said Washington believes Russia has killed dozens of Turkish military personnel in the course of its military operations in Syria. Speaking at a news conference at the State Department, Pompeo did not specify where or during which incident the Turkish soldiers were killed. It was the first time Washington has directly pointed its finger at Moscow over the death of Turkish soldiers. "We believe Russia has killed dozens of Turkish military personnel in the course of their military operations, and we stand with our NATO ally Turkey and we continue to consider additional measures to support Turkey and to end the violence in Idlib and in Syria more broadly," Pompeo said. Last month, an airstrike that Ankara said was carried out by the Syrian regime forces killed at least 34 Turkish soldiers, the deadliest attack on the Turkish army in nearly 30 years. The attack came after Russia-backed Syrian regime forces had intensified their campaign to retake Idlib, the last opposition-held stronghold in the country. That prompted Turkey, which backs some opposition factions looking to oust regime leader Bashar Assad, to mount a counter-offensive to repel their advances. Turkey and Russia, which back opposing sides in Syrias war, agreed on March 5 to halt hostilities in the countrys northwest after a recent escalation of violence displaced nearly a million people and brought the two sides close to confrontation. The ceasefire has largely held since then.