The case has sparked an outcry in France from journalists, who say that their sources must be protected.

Investigative website Disclose published a series of articles in 2021, including one in which it alleged that the Egyptian state used a French counter-intelligence operation in Egypt, codenamed "Sirli", for a "campaign of arbitrary executions" against smugglers on the Libyan border.

Disclose claimed that French forces were involved in at least 19 strikes against civilians between 2016 and 2018.

A journalist who co-wrote the article, Ariane Lavrilleux, was however not to be tried as the report was deemed of "public interest", the source said.

Prosecutors had in August urged the military member be tried for the lesser charge of "breach of professional confidentiality", but the investigating magistrate on October 9 ordered he go to court in May next year charged with "leaking defence secrets", it added.

The Paris prosecutor's office confirmed the trial had been ordered, but it said that it had on Monday appealed the magistrate's decision to try him on the more serious charge.

The engineer, who was formally charged and placed under judicial surveillance in 2023, has denied any wrongdoing.

His lawyer, Margaux van der Have, dismissed the allegations, saying they were not based on any "established facts", but rather the "probability" of a leak.

- 'Relief' -

The journalist, Lavrilleux, was arrested in 2023, sparking outrage among fellow journalists and raising questions about how the government employs controversial laws on issues of national secrecy in a country that is supposed to cherish the right to freedom of expression.

She spent 39 hours in detention, repeatedly interrogated by domestic intelligence agents for simply, she said at the time, doing her job.

But she escaped any formal charge earlier this year.

"Disclose and I have been exonerated after years of investigation. It's a relief and even a victory," Lavrilleux said.

Amnesty International secretary general Agnes Callamard, at the time of the arrest, described it as "chilling" and as part "of a wider attack on public interest journalists who attempt to expose the opaque actions of the French intelligence services".

"If we don't protect sources, it's the end of journalism," Lavrilleux said.

Disclose published a series of articles in November 2021 called the "Egypt Papers".

Another one alleged that three French companies, with the tacit agreement of the authorities, installed a massive cyber-surveillance system that enabled unprecedented repression of Egyptian civil society.

After the "Sirli" report, two NGOs last year filed complaints with the European Court of Human Rights against France for helping Egypt with intelligence they say was used to kill civilians.

Egyptians Abroad for Democracy and Code Pink-Women For Peace said that a refusal by the French judiciary to launch an investigation on the basis of the report constituted a violation of human rights, notably the right to life and the right to a fair trial.