Turkish President Recep Tayyip Erdogan has said that membership in the European Union remains a 'strategic goal' for his country, despite the uneasy relationship with the 28-member bloc.

Turkey's president said on Monday that membership in the European Union remains a "strategic goal" for his country, despite the uneasy relationship with the 28-member bloc.

Recep Tayyip Erdogan was speaking in Istanbul before departing for the Bulgarian Black Sea resort of Varna to attend a likely arduous summit meeting with EU leaders.

Erdogan said he would urge the EU to remove "political and artificial" hurdles against Turkey's membership and revive stalled accession negotiations during talks with European Commission chief Jean-Claude Juncker and European Council president Donald Tusk.

"As Turkey, we have been continuing on our way with the goal of full [EU] membership despite all the mines that were planted on our path and barriers in front of us," he told reporters.

"Today, membership in the European Union remains a strategic goal for us," Erdogan added.

The summit comes amid an array of issues that have strained ties, including a dispute between Turkey and EU-member Cyprus over energy exploration in the Mediterranean.

Turkish warships have prevented a drillship from carrying out exploratory drilling on behalf of Italian company Eni southeast of Cyprus, in a move that the EU criticised.

Turkey objects to "unilateral" gas searches by ethnically divided Cyprus' Greek Cypriot-run government without the direct involvement of breakaway Turkish Cypriots.

The Cyprus government says a gas search is its sovereign right and will benefit all citizens.

The EU largely depends on Turkey to curtail the flow of migrants into Europe but has deep concerns over the state of democracy, human rights and freedoms in Turkey that have taken a turn for the worse after a 2016 failed military coup.

Turkey for its part, accuses EU nations of not backing Ankara's fight against "terror" groups, including outlawed Kurdish militants and a network led by a US-based Muslim cleric, who has been accused of masterminding the coup attempt.

"Unfortunately on this issue [fight against terrorism], we are hearing many statements from the European Union that are in contradiction with their own principles and that never fit into our partnership's principles," Erdogan said.