Istanbul - Turkish border gates are and will remain open for refugees heading to Europe, President Recep Tayyip Erdogan said, accusing the European Union of not honouring a 2016 deal under which Turkey bore the brunt of a Syrian refugee crisis.

Refugees have already crossed the border

More than 75,000 migrants had crossed the border via the province of Edirne, Turkish Interior Minister Suleyman Soylu wrote on Twitter.

In the province of Edirne there are border crossings to EU members Greece and Bulgaria. However, initially neither Sofia nor Athens reported the arrival of such large numbers of migrants.

Turkish state broadcaster TRT showed footage of refugees, including children, crossing the border river in rubber dinghies into Greece. As many as 3,000 people, including babies, spent the night out in the cold and rain while local authorities and non-governmental organizations provided food, state news agency Anadolu reported. Some lighted camp fires and made temporary shelters, using wood from the nearby forested area, it said.

Anadolu showed footage of refugees climbing over the fences to the Greek side. Some refugees were seen running and others desperately trying to cover their faces as Greek police responded with tear gas. At least three were hospitalized in Edirne, Anadolu reported.

A map shows the EU-Turkey border zone

Turkey accuses the  EU

Erdogan criticized the European Union for not adhering to a 2016 deal to send financial aid in return for Ankara blocking a refugee influx into the bloc. "The European Union has to keep its promises," he said.

But European Council President Charles Michel fired back that it is "actively engaged" in efforts to uphold the deal, following a telephone conversation with Erdogan. He has also been in close contact with the Greek and Bulgarian prime ministers and highlighted the bloc's efforts to help both countries "protect the EU's external borders," he said in a statement.

Erdogan has repeatedly threatened to open the borders for refugees into Europe unless sufficient international aid is provided. However, the European Commission insists that it has already committed to spending the full 6 billion euros (6.62 billion dollars) promised under the deal.

Of this, 3.2 billion euros has been disbursed and a further 1.5 billion euros is already tied up in contracts, EU foreign policy spokeswoman Ana Pisonero said.

Turkey, which already hosts 3.6 million Syrian refugees, is concerned about a new massive refugee influx from Syria, where fighting has escalated in the flashpoint Idlib province, which borders Turkey.

Turkish troops killed in airstrike

Steady advances by the Syrian government and its Russian allies into the embattled province have displaced nearly 950,000 people, who are fleeing to Turkey's border.                              "We cannot bear the burden of a new refugee influx," Erdogan said.

Thirty-six Turkish troops were killed in an air raid in Idlib, Ankara's largest single-day military loss in Syria during the war.

Turkey destroyed Syrian chemical weapons facilities and military sites in retaliation for the air raid, Erdogan claimed, threatening further military action. The British–based Syrian Observatory for Human Rights reported that at least 74 fighters and allied militants died in less than 48 hours.  Syria's state news agency SANA accused Erdogan of exaggerating the extent of the damage.

Erdogan had threatened to drive Syrian troops out unless they withdraw from areas in Idlib - where some of the Turkish military observation posts are stationed.

Turkey blames Moscow

Turkey, which supports the rebels in Syria's civil war, blamed the deaths of its troops on Russian-backed Syrian government forces. Moscow, which supports the government of Syrian President Bashar al-Assad and is also conducting strikes in Idlib, denied any involvement.

The Turkish president said he told Russian President Vladimir Putin, "Get out of our way and leave us alone with the regime," in Syria, referring to his phone call with Putin. The two leaders agreed to meet in person as soon as possible, the Turkish government said, without citing any venue or timing.

Erdogan and Putin could meet either on March 5 or 6, TRT quoted Turkish Foreign Minister Mevlut Cavusoglu as saying in Qatar. Erdogan also spoke by phone to Iranian President Hassan Rowhani about Idlib, state news agency Anadolu reported. Iran is a key backer of the Syrian government.