Turkish President Recep Tayyip Erdogan on Friday lashed out at a French reporter who asked him about claims that Ankara sent arms to Syria.

Erdogan told the journalist he was talking like a member of an outlawed group blamed for last year's failed coup in Turkey.

At a joint press conference with French President Emmanuel Macron after their talks in Paris, the reporter asked the Turkish leader about a story from 2015 in the Cumhuriyet newspaper which allegedly proved Turkey had sent weapons to Syria.

Erdogan has always pinned the scandal on the exiled US-based preacher Fethullah Gulen.

Turkey blames Gulen for the 2016 failed coup and accuses him of running a group called the Fethullah Terror Organisation (FETO). Gulen denies the charges.

"Those are the words of FETO. You should learn not to speak with the words of FETO," Erdogan told the journalist after asking him to repeat the question.

The journalist could be heard insisting in French: "I am speaking as a journalist!"

"When you ask your questions, be careful on this point. And do not speak with the words of another," warned the Turkish leader.

"And I want you to know, you do not have someone before you who will easily swallow this," Erdogan added.

The issue had first erupted in January 2014 when prosecutors in southern Turkey uncovered trucks heading to Syria that they said were National Intelligence Organisation (MIT) vehicles stuffed with arms.

Ankara later charged those involved in the probe with membership of the Gulen movement.

"Those who carried out those operations were Gulenist prosecutors. Now they are in prison," said Erdogan icily.

In an apparent reference to American arms supplies to Syrian Kurdish militia that have angered Turkey, he added: "You ask me that question but why don't you ask me why the United States sent 4,000 trucks with arms to Syria?"

"You are a journalist, right? You should have looked into that as well."

Without confirming the incident, Erdogan said that the MIT had "every right" to carry out its operations.

- 'Terror has gardeners' -

Earlier the Turkish president had said terror was not formed by itself. "Terror and terrorists have gardeners. These gardeners are those seen as 'thinkers'.

He said "these people" nurture terror with newspaper columns "and one day, you will find, these people will be revealed as terrorists."

Erdogan's trip to Paris to meet Macron was his most important bilateral visit to an EU state since the failed putsch. It was overshadowed by questions about press freedom.

The P24 press freedom group says there are 151 journalists behind bars in Turkey, most of whom were arrested under the state of emergency in place since July 2016.

The issue was raised at the talks, with Macron telling Erdogan to "respect the rule of law".

The Cumhuriyet story resulted in its then editor-in- chief Can Dundar being handed a five-year and 10-month jail term for divulging state secrets. He later fled Turkey.