A defiant President Tayyip Erdogan on Sunday stepped up his attack on the European Union, saying Turkey had to go its own way and vowing to bring back the death penalty if parliament passes it.

Erdogan, who was at the opening ceremony for a memorial dedicated to the roughly 250 people who died during last year's failed coup, accused Brussels of "messing about" with Turkey's decades-long bid to join the bloc.

The speech, in front of the presidential palace in Ankara in the early hours of Sunday, wound up a marathon session of public appearances by Erdogan in both the capital and Istanbul to mark the anniversary of last year's failed coup.

"The stance of the European Union is clear to see... 54 years have passed and they are still messing us about," he said, citing what he said was Brussels' failure to keep promises on everything from a visa deal to aid for Syrian migrants.

"We will sort things out for ourselves, there's no other option."

Ties with Europe were strained after the coup, given the West's alarm about the scale of the government crackdown that followed. Some 150,000 people have been sacked or suspended from their jobs and more than 50,000 detained on suspicion of links to the U.S.-based Muslim cleric Fethullah Gulen, whom Ankara blames for the attempted putsch.

He also said he would approve, "without hesitation" the death penalty, if parliament voted to bring it back -- a move that would effectively end Turkey's bid to join the European Union.

"I don't look at what Hans and George say. I look at what Ahmet, Mehmet, Hasan, Huseyin, Ayse, Fatma and Hatice say," he said, to cheers from a flag-waving crowd.

Erdogan, the most popular and divisive politician in recent Turkish history, sees himself as the liberator of pious millions who were deprived for decades of their rights and welfare by Turkey's secular elite.

'RIP THE HEADS OFF'

European Commission chief Jean-Claude Juncker said the EU remained committed to dialogue with Turkey and called on Ankara to strengthen democracy and the rule of law. He also warned against reinstating the death penalty.

"One year after the attempted coup, Europe's hand remains outstretched," Juncker wrote in Germany's Bild am Sonntag newspaper.

"If Turkey were to introduce the death penalty, the Turkish government would finally slam the door to EU membership."

Addressing a crowd of hundreds of thousands in Istanbul on Saturday evening, Erdogan promised violent retribution against Turkey's enemies, including FETO - his term for Gulen's network - and the outlawed Kurdistan Workers Party (PKK).

"We know who is behind FETO, the PKK and all of them," he said. "We cannot defeat the queen, king, or sheikhs without defeating the pawns, knights and castles. Firstly, we will rip the heads off of these traitors."

He also said that alleged members of Gulen's network would be forced to wear jumpsuits like those worn by prisoners at the Guantanamo Bay detention camp, after one detainee showed up to a court hearing wearing a T-shirt that said "Hero".