Turkey will no longer stop refugees from reaching Europe, after dozens of its soldiers were killed in a regime airstrike in Syria, prompting Greece to tighten its sea and land borders amid reports hundreds were already on the move.

At least 33 Turkish soldiers perished and an additional 32 were injured in an overnight strike by Syrian government forces in the northwestern province of Idlib.

The killings, which took place near Turkey’s southern border, more than double Ankara’s death toll in Syria for February.

It has sparked fears that Turkey president Recep Tayyip Erdogan will launch a full-scale operation against Syrian government forces, which are backed by the Russian military – potentially locking Moscow and Ankara in a direct and deadly conflict.

Russia said on Friday it was sending two warships armed with cruise missiles to waters off the Syrian coast, local media reported, after officials blamed Ankara for the deaths of its soldiers.

Responding to the killings, Ankara ordered Turkish police, coastguard and border security officials to stand down on land and sea crossings towards Europe and allow refugees to pass.

"We have decided, effective immediately, not to stop Syrian refugees from reaching Europe by land or sea," said the Turkish official, who requested anonymity.

Turkey opens borders to allow refugees to flee to Europe Show all 17 1 /17 Turkey opens borders to allow refugees to flee to Europe Turkey opens borders to allow refugees to flee to Europe NGO members help 15 Afghan refugees, 5 children, 3 women and 7 men, to disembark from a dinghy as it lands ashore the Greek island of Lesbos on 28 February AFP/Getty Turkey opens borders to allow refugees to flee to Europe A group of migrants walk through the Turkish-Greek border in a village near the border city of Edirne, Turkey, on 28 February Reuters Turkey opens borders to allow refugees to flee to Europe Migrants from Afghanistan arrive on a dinghy on the Greek island of Lesbos on 28 February Reuters Turkey opens borders to allow refugees to flee to Europe Afghan refugees stand on the shore of the Greek island of Lesbos after disembarking a dinght on 28 February AFP/Getty Turkey opens borders to allow refugees to flee to Europe A group of migrants walk through the Turkish-Greek border in a village Bosnakoy near the border city of Edirne, Turkey on 28 February Reuters Turkey opens borders to allow refugees to flee to Europe Migrants from Afghanistan arrive in a dinghy at the village of Skala Sikaminias, on the Greek island of Lesbos on 28 February AP Turkey opens borders to allow refugees to flee to Europe Afghan refugees stand on the shore of the Greek island of Lesbos after disembarking a dinght on 28 February Reuters Turkey opens borders to allow refugees to flee to Europe A group of migrants walk through the Turkish-Greek border in a village near the border city of Edirne, Turkeythrough the Turkish-Greek border in a village Bosnakoy near the border city of Edirne, Turkey Reuters Turkey opens borders to allow refugees to flee to Europe Refugees walk near fences enforcing the Greek border as they try to enter Europe, in Edirne, Turkey on 28 February 2020. the Turkish government announced its decision to no longer stop refugees from reaching Europe, after 33 Turkish soldiers were killed in Idlib, Syria on 27 February. EPA Turkey opens borders to allow refugees to flee to Europe Refugees walk near fences enforcing the Greek border as they try to enter Europe, in Edirne, Turkey on 28 February 2020. the Turkish government announced its decision to no longer stop refugees from reaching Europe, after 33 Turkish soldiers were killed in Idlib, Syria on 27 February. EPA Turkey opens borders to allow refugees to flee to Europe Refugees walk near fences enforcing the Greek border as they try to enter Europe, in Edirne, Turkey, 28 February 2020. the Turkish government announced its decision to no longer stop refugees from reaching Europe, after 33 Turkish soldiers were killed in Idlib, Syria on 27 February. EPA Turkey opens borders to allow refugees to flee to Europe Refugees walk near fences enforcing the Greek border as they try to enter Europe, in Edirne, Turkey, 28 February 2020. the Turkish government announced its decision to no longer stop refugees from reaching Europe, after 33 Turkish soldiers were killed in Idlib, Syria on 27 February. EPA Turkey opens borders to allow refugees to flee to Europe Refugees walk near fences enforcing the Greek border as they try to enter Europe, in Edirne, Turkey, 28 February 2020. the Turkish government announced its decision to no longer stop refugees from reaching Europe, after 33 Turkish soldiers were killed in Idlib, Syria on 27 February. EPA Turkey opens borders to allow refugees to flee to Europe Greek soldiers patrol behind a border fence as refugees try to enter Europe, from Edirne, Turkey, 28 February 2020. the Turkish government announced its decision to no longer stop refugees from reaching Europe, after 33 Turkish soldiers were killed in Idlib, Syria on 27 February. EPA Turkey opens borders to allow refugees to flee to Europe Syrian refugees board a bus as they head to border villages of Edirne province, in Istanbul, Turkey, 28 February 2020. The Turkish government announced its decision to no longer stop refugees from reaching Europe, after 33 Turkish soldiers were killed in Idlib, Syria on 27 February. EPA Turkey opens borders to allow refugees to flee to Europe Refugees walk near fences enforcing the Greek border as they try to enter Europe, in Edirne, Turkey, 28 February 2020. The Turkish government announced its decision to no longer stop refugees from reaching Europe, after 33 Turkish soldiers were killed in Idlib, Syria on 27 February. EPA Turkey opens borders to allow refugees to flee to Europe Migrants wait in no-man land between Turkey and Greece, in Pazarkule, Edirne, Friday, Feb. 28, 2020. NATO envoys were holding emergency talks Friday at the request of Turkey following the killing of 33 Turkish soldiers in northeast Syria, as scores of migrants gathered at Turkey's border with Greece seeking entry into Europe. AP

"All refugees, including Syrians, are now welcome to cross into the European Union,” the official told Reuters.

Greek officials said the country is now tightening its sea and land borders with Turkey, and has reached out to the European Union and Nato about the matter.

Turkish news agency Demiroren said around 300 migrants, including women and children, had begun heading towards borders between Greece and Bulgaria and Turkey’s Edirne province at around midnight.

The same news outlet said that others also gathered on the western Turkish coastal district of Ayvacik in Canakkale province with the aim of travelling by boat to Greece's Lesbos Island.

Syrians, Iranians, Iraqis, Pakistanis and Moroccans were among those in the group, it said.

“All refugees should enjoy freedom of movement, but we are also deeply concerned that those leaving Turkey will face a perilous journey across the sea to Greece – a journey that has claimed so many lives,” said Refugees International president Eric Schwartz in a statement.

“Greece itself is ill-prepared to receive a sudden influx of refugees – thus, it critical that the EU support Greece and fast track refugees from Greece to other EU countries where they can seek asylum.”

Turkey has sent thousands of troops and heavy military hardware into Syria this month in support of some of the rebels, after the regime launched an offensive to take the last opposition stronghold in the war-ravaged country.

Nearly one million people have been displaced since 1 December, according to the United Nations. Sixty per cent of them children.

Mr Erdogan has repeatedly warned that Turkey will launch a full-scale offensive to repel Russian-backed Syrian forces unless they pull back from Turkish observation posts in the Syrian region.

The deaths of the Turkish soldiers will only escalate the messy conflict.

Turkey said it had responded to the attack on its troops by hitting 200 Syrian government targets, “neutralising" 309 Syrian soldiers and destroying air defence systems, tanks and helicopters.

Foreign secretary Dominic Raab said he “condemned” the killing of the Turkish soldiers.

“We support our Nato ally Turkey’s efforts to negotiate an immediate and lasting ceasefire in Idlib, which is imperative if this already dangerous situation is not to deteriorate further.

“Yesterday’s events only confirmed the reckless and brutal nature of the offensive which the Syrian regime and Russia are conducting in Idlib. This has created the gravest humanitarian crisis of the entire war.”

Ambassadors from the Nato military alliance are set to hold emergency talks on Friday in Brussels at Turkey's request to discuss the crisis.

Stephane Dujarric, spokesman for the UN’s secretary general said the UN was following the situation with “grave concern”.

Turkey’s state-run Anadolu agency said that the killings happened despite coordination with Russian officials on the ground, and that the attacks continued after a warning being made after the first strikes.

Russia’s defence ministry, as cited by the RIA news agency, refuted that saying that Ankara had failed to notify Moscow of the presence of Turkish troops in the area despite being in regular communication.

The statement claimed that Turkish troops had been hit by artillery fire from Syrian government forces who were trying to repel an offensive by rebel forces.

It added Russian war planes had not carried out any air strikes in the area at the time and Moscow did everything it could to help once it learnt of the Turkish troop presence.

In a separate Russian media report, Moscow later responded by saying it would send additional military hardware – including warships equipped with Kalibr cruise missiles – to Syria’s cost.

Turkey’s decision to open the way for refugees to travel Europe would, if executed, reverse a pledge Turkey made to the European Union in 2016.