No European country has the luxury of ignoring the Syrian Civil War or the humanitarian tragedy unfolding in its wake, President Recep Tayyip Erdoğan said Monday after a meeting with NATO Secretary-General Jens Stoltenberg.

Speaking at a joint press conference ahead of another meeting with European Commission President Ursula von der Leyen, Erdoğan said Ankara expected tangible support from its allies for Turkey’s Syria campaign.

"NATO is at a critical time to show clear solidarity with its allies," he said.

Criticizing Greece’s attitude towards migrants at its borders, Erdoğan blamed Athens of trying to exploit the situation to secure unmerited gains.

"It is beyond reason and comprehension for an ally and a neighboring country [Greece] to blame Turkey for the migrant wave. I clearly pointed out to Mr. Secretary-General that we won’t allow this country to exploit this issue or the EU for undeserved gains," he said.

Stoltenberg also expressed his concerns over the security situation in Syria and the resulting migrant crisis.

"The Assad regime and Russia caused untold civilian suffering," he said, adding that he hopes the cease-fire in Idlib, northwestern Syria reached last week by Turkey and Syria will grow into a standing peace.

The secretary-general called migration "a common challenge" and hailed the dialogue between Turkey and the EU to find a long-term solution for the crisis.

After the meeting between Erdoğan and von der Leyen, the Turkish presidency described their talk as "productive" and having concluded "on time."

The meeting comes at a critical time. Relations between Ankara and Brussels remain strained after Turkey’s decision to allow refugees and migrants without proper paperwork to cross through its borders to Europe.

Tens of thousands of asylum-seekers have been trying to cross the land border between Turkey and Greece for a week after Ankara announced it would no longer prevent people from trying to cross into the European Union.

"Finding a solution to this situation will require relieving the pressure that is put on the border," von der Leyen told a news conference Monday.

She said ensuring the right to asylum, support for both Turkey and Greece, and moving migrants – especially minors – stranded on the Greek islands to mainland Europe were immediately needed, as well.

It has been 11 days since migrants flocked to the Turkish border in northwestern Edirne province to wait for the EU to open its gates for passage. More than 3,000 refugees continue to wait hopefully despite staying out in the open in cold weather.

The provincial migration office of the Governorate of Edirne is meanwhile distributing three meals a day to refugees, while medical staff tries to treat those who have been affected by tear gas thrown by the Greek side.

As a response to the lack of humanitarian and financial aid for refugees from the international community, Erdoğan warned European countries that Turkey could not handle a new migration wave and would have to open its borders in the case of another influx, allowing hundreds of thousands of migrants to head toward Europe.

Around 116,000 refugees and migrants are currently living in Greece, according to figures from the U.N. Refugee Agency (UNHCR).

Among them are an estimated 5,500 unaccompanied minors, according to Greece's National Center for Social Solidarity (EKKA). Many of them are living in extremely cramped and unsanitary conditions.