Refusal to heed the ruling could fuel tensions between Turkey and the European Union already heightened over Ankara’s search for energy in the contested waters of the eastern Mediterranean.

The European Court of Human Rights on Tuesday ordered Turkey to free Selahattin Demirtas, a former leader of the pro-Kurdish party HDP, upholding an earlier ruling. Demirtas’s rights, including freedom of expression and the right to liberty and security, had been violated, it said.

The decision is binding on Turkey but the country hasn’t complied with some of the court’s previous verdicts, and on Wednesday Erdogan signaled that may happen again.

 “We do not have to tolerate so many double standards and hypocrisy any more,” he said of the ruling.

The court also ordered Turkey to pay Demirtas 60,400 euros ($73,600) in damages and expenses.

Under Demirtas, the HDP won an unprecedented 80 seats in a mid-2015 parliamentary election, denying Erdogan’s AK Party a majority for the first time in its then nearly 13-year rule. In a re-run vote, the AK Party regained its legislative majority.

The following year, authorities launched a crackdown on the HDP, stripping its lawmakers of their immunity from prosecution and arresting several top members, including Demirtas.

Along with Figen Yuksekdag, a co-chair of the HDP, Demirtas was accused of encouraging Kurds to protest over Turkey’s failure to stop Islamic State attacks on the Syrian Kurdish town of Kobani in 2014. At least 37 people died in violence during the demonstrations.

Turkish courts have also charged the two with having ties to the outlawed Kurdish militant group PKK, which sent fighters to battle Islamic State in Kobani and elsewhere in Syria. The PKK is recognized as a terrorist group by the EU and the U.S. Demirtas denies the charges.

 “This person is guilty in the eyes of our nation, not because of his political rhetoric, but because he could not distance himself from terrorism and caused the deaths of dozens of people on the orders of the separatist terrorist organization,” Erdogan said in reference to Demirtas and the PKK.

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