German Chancellor Angela Merkel said on Tuesday that she would press for implementation of the deal between European Union (EU) and Turkey at a summit this week.
She said the alternative of closing borders to limit the flow of refugees to Europe would have dire consequences for the bloc.
Speaking at a news conference with Israeli Prime Minister Benjamin Netanyahu, Merkel said that the summit was not about agreeing new quotas for distributing refugees across Europe, saying this would be "laughable" given that less than 1,000 have been relocated under an existing scheme.
Instead, she said it was about whether the EU-Turkey pact could successfully tackle the causes of the refugee flow or whether the bloc should "give up and instead close the Greek-Macedonian-Bulgarian border with all the consequences that would have for Greece, the European Union and the Schengen zone."
"I will fight with all my strength on Thursday and Friday for the EU-Turkey agenda as the right way to tackle this," she added.
Turkey is a transit point for refugees aiming to reach European countries from Syria and Iraq because of its geography bridging the Middle East and Europe.
As a result, Turkey is central to Merkel's diplomatic efforts to reduce the number of asylum-seekers coming to Germany. She has long resisted pressure for unilateral measures such as a national cap on refugee numbers.
Following her recent visit to Turkey, Prime Minister Ahmet Davutoglu said that they would inform Brussels in coming days on the initial projects it plans after receiving 3 billion euros in funds from the EU, aimed at curbing record flows of refugees to Europe through Turkey.
Syrian refugees escaping the violence in their country fled Syria in large numbers following the escalation of the Syrian Civil War in 2012.
One of their most preferred destinations was neighbouring Turkey, which hosts the most Syrian refugees in the world according to registration records of the United Nations.
Turkey has spent nearly $10 billion of its own resources on the refugees whose number in the country has been climbing to 2.7 million people.
Tens of thousands of Syrians, since early February, have reportedly been fleeing to the Turkish border, after recent attacks by Russian-backed Syrian regime forces and its allies in Aleppo's northern countryside, cutting opposition supply lines to Turkey and swelling refugee numbers in the area to 100,000.
During the civil war, nearly 8 million Syrians are displaced internally while at least 5 million have fled the country to the neighbouring countries of Turkey, Lebanon, Egypt and Jordan.