"France is potentially an accomplice to serious violations of humanitarian laws by selling weapons and military equipment to Saudi Arabia", said Aurelie Perrier from Amnesty International at a protest near the Eiffel Tower.
A Yemeni rights group on Tuesday filed a lawsuit against Prince Mohammed in France, accusing him of complicity in torture and inhumane treatment in Yemen, lawyers said.
PARIS-Crown Prince Mohammed bin Salman of Saudi Arabia wrapped up his first official visit to France by meeting Tuesday with President Emmanuel Macron on defence, security and economic issues - and to share their concerns over the apparent use of chemical weapons in Syria.
On Yemen, where Saudi Arabia has led an global military coalition since 2015 and waged a blockade that has sparked widespread condemnation.
Qassemi said the Saudis should have this point in mind that they can not change their doomed fate by playing the blame game, buying security and sponsoring terrorist groups.
Macron stressed the need for "respect for worldwide humanitarian law".
"We will not tolerate ballistic missiles activities that threaten Saudi Arabia", Macron said. Several rights groups also have warned of possible legal action if the government does not halt its sales.
The Iranian Foreign Ministry spokesman expressed hope that France must have reminded the Saudi leaders of the fate of previous Middle East dictators and aggressors in the region.
Macron is only eight years older than the prince.
Prince Saud al-Faisal, who served as Saudi Arabia's foreign minister for 40 years until his death, was a regular visitor to the French capital, where he stayed in the lap of luxury.
Saudi national company Aramco and French oil giant Total announced a deal earlier Tuesday to build a petrochemical complex in Jubail in Saudi Arabia.
Macron waded into a regional crisis last November when Lebanon's Prime Minister Saad Hariri tendered his resignation on live television from Riyadh, apparently under pressure from the crown prince.