Turkish President Recep Tayyip Erdogan has once again threatened that migrants will resume crossing into Europe if visa-free travel demands are not met.

It has been a turbulent week in Turkey after the resignation of Prime Minister Ahmet Davutoglu, and the continued consolidation of power of President Erdogan may be putting the migrant deal between the European Union (EU) and Turkey in danger.

While this is not the first time that the Turkish president has threatened to scrap the deal, due to the resignation of the Prime Minister and a June deadline for visa-free travel looming it may be more serious this time.

Burhan Kuzu, a deputy in Mr Erdogan’s AKP party, has warned European leaders that they should consider their decisions carefully, remarking on Twitter, “when they pick the wrong decision, we will release the refugees,” N-TV reports.

The EU made clear that visa-free travel could only happen if 72 conditions were met by the Turks, which the former Prime Minister had agreed to. Now that the Prime Minister is gone and Erdogan looks toward a referendum to potentially merge the powers of both offices, the future of the deal seems ever more uncertain.

One of the main obstacles for Mr Erdogan has been the EU’s demand for Turkey to change its current terrorism laws that many feel is leading to heightened conflict with Turkey’s Kurdish minority. The laws also allow the persecution of journalists and academics even if there are no terrorist related allegations. The Committee on Civil Liberties and Justice in the EU Parliament has been requested by the EU Commission to provide rapid advice on the subject.

While the migrant deal has stemmed the flow of much of the migrants from Turkey into Greece, various European leaders are not keeping their hopes up about the longevity of the deal due to the demands made by Ankara.

EU Parliament President Martin Schulz has said he does not see any chance of a visa-free agreement by the June deadline. Mr Shulz told German radio that it was “out of the question” for the parliament to even begin discussions on the issue before the conditions were met. He said that two of the key demands regarding terror laws and data protection had not even been looked at by Ankara – much less them meeting the EU’s standards.

Austrian Foreign Minister Sebastian Kurz has gone further saying that the EU needs to look for a plan that may not involve Turkey at all. In Vienna on Wednesday Mr Kurz stated at a press conference, alongside Greek Foreign Minister Nikos Kotzias, “although there is now a certain relaxation, the Turkey deal is something we have to be careful about, that we do not become dependent on Turkey.”

Mr Kotzias expressed a more hopeful attitude toward the deal but stressed the importance of the Mr Davutoglu’s resignation saying, “I think there are internal developments in the political system of Turkey, and I hope that it has no negative impact on the relations between the two entities.”

Mr Kotzias also took the opportunity to criticise the non-governmental organisations (NGOs) and aid workers who incite violence and create chaos in Greek migrant camps. He stated that some of them are nurturing “illusions” among the migrants about what Europe will be like for them and that many are simply “trying to make as much money as possible.”