The EU and Turkey agreed to review a deal signed in 2016 on managing migrants to try to settle a dispute that sent thousands of people to the Turkey-Greece border in hopes of reaching Europe, top EU officials said on Monday.
Under the 2016 deal, Turkey prevented displaced Syrians from entering the EU through Greece.
Brussels promised to pay €6 billion to Turkey if it helped to curb migrant flows.
The deal helped to stop Europe’s biggest refugee influx since the Second World War.
After talks with Turkish President Recep Tayyip Erdogan in Brussels on Monday, European Council President Charles Michel said teams led by the EU foreign policy chief and Turkey’s foreign minister would work together on the deal.
European Commission President Ursula von der Leyen said that during the talks with Mr Erdogan “there was a clear focus on, ‘let’s discuss what is fact. Let’s sort out how both sides see the past and how we evaluate the EU-Turkey statement’.”
But senior EU officials warned there was a lot still to discuss as they demanded Ankara continue to implement their 2016 migrant deal.
Mr Erdogan sought more support from the EU to handle the migrant crisis but was told to stop encouraging refugees to cross into Greece.
“We have different opinions on different things and that is why it is important to have a frank and open dialogue,” Mr Michel said in Brussels.
Officials from both sides will now work “to be certain we are on the same page", Mr Michel said.
Tension between Turkey and the EU has risen over the past week after Ankara publicly told millions of migrants and asylum seekers that it would not stand in their way if they wanted to head to Europe.
Turkey urged Greece to open its border after about 35,000 migrants reached the Turkish border with the EU.
In recent months, Mr Erdogan has accused the bloc of not supporting his military action in Syria and said the true cost of housing refugees in his country was about €40bn.
Ms von der Leyen has accused him of politicising the border to gain EU concessions.
“It remains valid and we need to implement missing elements,” Ms von der Leyen said, acknowledging that it was the EU’s responsibility as well as Turkey’s.
“We have indicated to President Erdogan that we are willing to move forward as long as it is reciprocal.”
Mr Erdogan has demanded more funding from the EU and for it to make good on its pledge of visa-free travel for Turkish citizens in return for keeping refugees within his country.
He knows European governments are aware that the 2015 migration crisis helped to fuel populism and anti-EU sentiment across the bloc.
Mr Erdogan also held talks with Nato secretary general Jens Stoltenberg on Monday, where the Turkish leader said he wanted western allies to support the country in coping with the millions of refugees from Syria.
"The crisis stemming from Syria, with its security and humanitarian aspects, is threatening our region and even all of Europe," Mr Erdogan said.
"No European country has the luxury to remain indifferent."