PARIS (AFP) - The French presidency has written to Emmanuel Macron's disgraced former bodyguard Alexandre Benalla raising concerns over his recent work as a "consultant" in Africa, according to the letter seen by AFP on Thursday (Dec 27).

Benalla faces criminal charges after it emerged in July that he roughed up protesters during a May Day demonstration in Paris while wearing a police helmet.

The "Benalla affair" sparked a major scandal for Macron, prompting a wave of accusations from opponents that the presidency covered it up.

Benalla, 27, was swiftly fired after the revelations, but officials are worried he may since have been profiting from his former insider status.

Two weeks ago, it emerged that Benalla travelled to Chad in early December and met with President Idriss Deby, shortly before Macron himself paid a visit to the African country.

Benalla said he was accompanying a "foreign business delegation" promoting major Middle Eastern companies.

But the fresh revelations have sparked questions in France over why he was granted such high-level access to an African leader.

Macron's office told AFP that Benalla had not informed the presidency of the trip until afterwards.

In a strongly worded letter to Benalla dated Dec 22, Macron's office chief Patrick Strzoda warned the former bodyguard against divulging any confidential information gleaned during his previous job at the French president's side.

"Let us be clear: we forbid you from claiming you have any kind of recommendation or tacit support from the presidency," Strzoda wrote.

"With regard to your current personal activities, we ask you to ensure they are conducted with strict respect for the confidentiality and ethical responsibilities of your time in this office."

Strzoda further demanded that Benalla provide details of "personal and private trips" during his time working with Macron, including any payments.

The presidency would be forced to respond to any previously undisclosed business dealings deemed "incompatible" with his former role, Strzoda warned.

'I WON'T KEEP QUIET'

Benalla has denied boasting of insider influence to win work after his sacking and accused members of Macron's entourage of "trying to wreck" his life.

"I won't keep quiet any longer," he said in a statement on Wednesday.

Le Monde newspaper reported that Benalla had met in October with Congo President Denis Sassou-Nguesso, as well as with top officials in Cameroon as part of a business delegation.

"Today, I'm doing consulting work. I'm working in around 10 countries in Africa," Benalla told the newspaper.

Benalla, a former bouncer, became Macron's chief bodyguard during his 2017 election campaign and was given a senior security job upon his victory.

He faces charges of assault, impersonating an officer, and illicitly receiving CCTV recordings of the May Day incident.

He has denied any wrongdoing, insisting he was simply trying to help police deal with violent protesters.

The Benalla scandal has reared its ugly head again at an unwelcome time for Macron, following a wave of protests against him by the "yellow vest" movement.