Activists have called for the European Union to use a meeting with the Turkish foreign minister to urge the release of human rights workers detained as part of Turkey’s crackdown following last year’s failed coup.
The issue was raised during a noisy protest in Brussels ahead of the talks, amid growing concern that Turkey is sliding away from EU values as President Recep Tayyip Erdogan tightens his grip on power and cracks down on perceived opponents.
Amnesty International secretary general Salil Shetty said: "Our call is very simple. We want the unconditional and immediate release of these human rights defenders."
Amnesty’s Turkey director and chair, Idil Eser and Taner Kilic, are among those being detained.
Mr Shetty added after handing a petition to EU foreign affairs chief Federica Mogherini: "Turkey has to get a clear message that the EU would like to reset its relationship with Turkey and that there will be consequences for the actions they take, because right now they feel no consequences."
The talks in Brussels between Ms Mogherini and Turkey’s foreign minister Mevlut Cavusoglu and EU affairs minister Omer Celik come as Turkey’s long-standing bid for EU membership remains in deep freeze and shows no sign of thawing.
More than 50,000 people, including journalists and opposition MPs, have been detained since the July 15 2016 coup attempt.
Critics say the crackdown initially targeted people suspected of links to the failed coup, but has expanded to include government opponents.
Turkey applied to join the EU three decades ago, and they started negotiating in 2005.
But of the 16 negotiating chapters on issues as varied as capital movement and food safety, only one - science and research - has been provisionally closed.
Tuesday’s discussions in Brussels are expected to touch on issues including Ankara’s EU accession, immigration, Turkey’s demands for visa-free travel for its citizens, the fight against terrorism and energy and trade ties.
Last week, the German government increased pressure on Turkey after the jailing of a human rights activist, telling all citizens travelling there to exercise caution and threatening to withhold backing for German investments in Turkey.
Based on previous rounds of talks between lower level officials, the meeting on Tuesday could become heated.
In reference to Germany’s tense relations with Turkey, European Commissioner Johannes Hahn said: "We have fundamental criticism about the lack of rule of law and that is something that doesn’t just depend on one specific member state.
"It’s a fundamental issue that must be raised and will be raised by us."