The relaunching of cooperation between the European Union and Turkey depends on President Recep Tayyip Erdoğan acting constructively and continuing to de-escalate tensions over Turkey's gas exploration in the eastern Mediterranean, an official from the bloc told Agence France-Presse.
The EU's top two officials will head to Turkey on April 6 to lay out to Erdoğan the bloc's conditions for improved ties after a dip in tensions.
European Council president Charles Michel and European Commission chief Ursula von der Leyen will hold out the prospect of key economic and diplomatic gains for Ankara, including more funding for Turkey's hosting of millions of Syrian refugees.
The roadmap for relaunching cooperation - agreed by EU leaders at a summit last month - depends on Erdoğan's attitude.
An EU official said the meeting in Ankara "will not be the moment for negotiations, but will provide a framework" on the way forward.
The bloc has been encouraged by conciliatory moves from Ankara over the past few months, including the resumption of talks with Greece over a disputed maritime border and steps to restart UN peace efforts for divided EU member state Cyprus.
Brussels' "carrot-and-stick" approach entails the possibility of modernizing a customs union, liberalizing visa rules, more money for Syrian refugees and a resumption of high-level dialogues on topics from security to health.
But any steps would be "phased, proportionate and reversible," and if Ankara backtracks then the EU has warned it could slap painful sanctions on the country.
"If Erdoğan does not show himself to be cooperative then everything will be blocked," the official warned.
Convincing the Turkish leader to accept the conditions will not be easy and he has already pressed the EU to move faster towards "concrete results."
'Erdoğan has become more pliant'
But analysts and diplomats say Erdoğan has become more pliant in the face of economic woes at home and a toughening line from Washington after his ally Donald Trump was voted out of the White House.
EU members have been split over how to handle Turkey, with Cyprus, Greece and France urging a tough line while others, led by economic powerhouse Germany, want more engagement.
Ankara formally opened talks to join the bloc in 2005 but that process has become frozen as Erdoğan tightened his grip over the country.
The bloc's foreign policy chief Josep Borrell insists the latest offer of cooperation from the bloc's leaders "could be a new chapter in EU-Turkey relations" after last year's nadir.
"The situation remains fragile, but the EU welcomes these forthcoming developments and gestures on the part of Turkey and has responded by extending its hand," he wrote.
EU leaders remain deeply wary of Erdoğan and there are major concerns on rights after Ankara's recent withdrawal from the Istanbul Convention - a global treaty on violence against women - and moves to ban pro-Kurdish Peoples' Democratic Party (HDP).
But these worries have not put the brakes on the attempted rapprochement with Turkey.
Central to the relationship is Turkey's role hosting four million refugees from Syria.
Ankara is pressing Brussels to update a deal struck five years ago to stop large-scale arrivals of migrants in the EU in return for billions of euros in aid.
Both sides accuse the other of violating the agreement - with Turkey saying the EU has not stumped up all the cash promised and Brussels insisting Ankara needs to accept back migrants who make it to the bloc.
The bloc is refusing to reopen the agreement but EU leaders tasked von der Leyen's commission to come up with a proposal on more money for Turkey as Brussels presses for Syrian refugees to be better integrated.
'Convergences of interest'
The EU also insists it wants to see Turkey "positively contribute" to solving conflicts in Libya, Syria and Nagorno-Karabakh in which Ankara plays a key role.
Borrell said that in Libya "convergences of interests are slowly starting to appear" after the installation of a transitional government.
Positions however appear to be diverging over Cyprus as the UN gears up for exploratory talks involving international players Turkey, Greece and Britain in April over relaunching peace efforts.
Erdoğan has backed harder-line Turkish Cypriot leaders pressing for a two-state solution, while both Brussels and EU member state the Republic of Cyprus want a bi-communal federation.
"The most healthy formula to the Cyprus problem is a peaceful divorce," a Turkish official told AFP. "A two-state solution and the start of meetings on this basis."