Turkish President Recep Tayyip Erdogan warned the EU on Monday to make a decision by year's end on his nation's stalled bid to join the bloc, or he would call a referendum on the matter.

"I say let's be patient until the end of the year and then go to the people," Erdogan said in televised comments. "Doesn't sovereignty belong to the people?"

Erdogan also raised the question in an interview published Sunday, saying "our patience is not endless."

"If need be, later, we could also consult our people," he told leading daily Hurriyet, alluding to the UK's Brexit referendum in June.

Turkey first applied to become a member of the EU in 1987 but the formal accession talks started only in 2005, with the negotiations bogged down in a number of disputes including Ankara's deteriorating human rights record.

The relations have been further strained in the wake of the July 15 failed coup attempt that has seen Ankara launch a vast crackdown on its alleged perpetrators.

Over 35,000 people including military officers, teachers and other public employees have been arrested.

More than 100 journalists have been put behind bars while 170 media outlets including newspapers have been closed down, according to journalists' unions -- in a clampdown that raised alarm in Europe.

Turkey last week slammed as "biased" an EU progress report that accused Ankara of backsliding on membership criteria and told the government to decide whether it was serious about accession.

European Parliament chief Martin Schulz became a target for Erdogan's criticism after he said the EU has to consider economic sanctions against Turkey for its crackdown of the dissent.

In an interview with Bild am Sonntag newspaper published on Sunday, Schulz said he was in favour of dialogue with Turkey in order to help support the opposition and prisoners.

"But as the EU, we will have to think about the economic measures we can take. By the end of the year, the customs union which Turkey is a part of must be reformed," he said.

"I cannot imagine that we will extend this customs union after the arrests of opposition lawmakers and journalists."

Erdogan responded on Monday, saying "Who are you? Since when do you have the authority to decide on behalf of Turkey?"

He called Schulz "rude" for pushing the EU to introduce sanctions against his government.