French leader Emmanuel Macron and Saudi Crown Prince Mohammed bin Salman agreed to work "to ease the effects" of the Ukraine war, Macron's office said Friday, after talks in Paris that marked the full diplomatic rehabilitation of the Saudi leader.

Like US President Joe Biden who visited Riyadh earlier this month, Macron had been keen to secure extra oil production from the de facto Saudi leader who was a pariah in the West until recently.

A French statement made no reference to any agreement during a dinner on Thursday night, but said the two men had agreed to "intensify their cooperation to ease the effects (of the war) in Europe, the Middle East and the world".

The meeting outraged rights groups because of bin Salman's suspected role in the murder of Washington Post journalist Jamal Khashoggi in 2018.

Western leaders snubbed the 36-year-old prince after Saudi agents killed Khashoggi inside Saudi Arabia's consulate in Istanbul.

But the heir to the Middle East's most powerful throne is being courted again as Europe and its allies urgently seek fresh sources of fossil fuels to replace lost Russian production.

As he left on Friday, bin Salman expressed his "deepest gratitude and appreciation for the warm reception and hospitality" in a statement posted online by the Saudi foreign ministry.

While Biden fist-bumped bin Salman as he arrived in Riyadh, Macron shook hands on the steps of the Elysee Palace as he welcomed the prince.

"He's shaking the hand for a long time of a man whose hands are covered in blood," senior left-wing MP Alexis Corbiere told BFM television on Friday.

Corbiere also took aim at bin Salman's role overseeing Saudi Arabia's military intervention in Yemen in 2015 against Iran-backed Huthi rebels.

Allies of the French president defended a meeting that has been portrayed as a case study in "Realpolitik" -- putting practical needs above principles in foreign policy.

Analysts say Saudi Arabia is one of few countries worldwide with the capacity to increase its oil production, though its margin for manoeuvre is seen as limited.

"There are partners, countries that do not all share the same democratic values as France," French Public Services Minister Stanislas Guerini, a close ally of the president, told Europe 1 radio.

"But I believe it would be a mistake to not speak, to not try to make things happen," he added.

"French values, the voice of France, human rights, were carried last night, as always, by the president," he added.

US intelligence agencies determined that bin Salman had 'approved' the operation that led to Khashoggi's death, although Riyadh denies this
US intelligence agencies determined that bin Salman had 'approved' the operation that led to Khashoggi's death, although Riyadh denies this AFP / Bertrand GUAY

Oil market analysts say an August 3 meeting of the OPEC oil cartel, of which Saudi Arabia is a key member, will be decisive in showing whether Western pressure for extra output bears fruit.

Amena Bakr from Energy Intelligence, a consultancy, told AFP the "most likely outcome is a modest increase or delay."

A US official told journalists on Thursday that "we're optimistic that there could be some positive announcements coming out of the next OPEC meeting."

Macron's decision to host the controversial royal sparked fierce criticism at home from human rights groups and left-wing opponents.

The head of Amnesty International Agnes Callamard told AFP she felt "profoundly troubled by the visit".

The killing of Khashoggi was described by a UN probe as an "extrajudicial killing for which Saudi Arabia is responsible".

US intelligence agencies determined that the crown prince had "approved" the operation that led to Khashoggi's death.

Riyadh denies this, blaming rogue operatives.

"I am scandalised and outraged that Emmanuel Macron is receiving with all the honours the executioner of my fiance, Jamal Khashoggi," his fiancee Hatice Cengiz told AFP on Thursday.

The French president travelled to Riyadh in December 2021 for further talks that again raised questions about his public commitment to promote human rights.

"The president will raise it (the human rights issue) in a way as to be the most effective possible, which requires a certain form of discretion," a presidential aide said ahead of the dinner.

"Individual cases" would be raised, the aide said, without confirming that Khashoggi would be mentioned.

The Saudi strongman stayed overnight at his Louis XIV chateau in Louveciennes west of Paris which he acquired in 2015, according to a source who asked not to be named.

The castle was built in 2009 by a company headed by Khashoggi's cousin Emad and was described as "the world's most expensive home" at the time of its purchase.