Israeli Prime Minister Benjamin Netanyahu is in Paris to commemorate the victims of a mass arrest of Jews in Nazi-occupied France in 1942.
More than 13,000 Jews were rounded up and detained at a cycling stadium, the Velodrome d’Hiver, before being deported to Nazi death camps.
Mr Netanyahu also held direct talks for the first time with French President Emmanuel Macron.
He is the first Israeli prime minister to attend the Vel d’Hiv commemorations.
“I’m here to mourn the victims,” Mr Netanyahu told an audience in Paris, which included Jewish group sand Holocaust survivors.
“Seventy-five years ago, a heavy darkness descended on this city… It seems the values of the French revolution – equality, fraternity, liberty – was crushed brutally under the boot of anti-Semitism.”
While warning against the dangers of modern extremism, he hailed the “great, great human beings” who had risked their lives to save Jews in France during Nazi occupation.
Out of the more than 13,000 Jews arrested by French police on 16 and 17 July 1942, about 4,000 were children.
The families were taken to the Velodrome D’Hiver, a cycling stadium near the Eiffel Tower, or an internment camp set up just outside the capital at Drancy.
They were then deported by train, mostly to Auschwitz concentration camp. Fewer than 100 people survived.
The episode remains controversial in France. Marine Le Pen, Mr Macron’s far-right opponent in this year’s election, drew strong criticism on 9 April when she suggested France was not responsible for the tragedy.
But speaking at the ceremony on Sunday, President Macron reaffirmed that “it was France that organised” the mass arrest.
The visit has drawn consternation from critics of the Israeli PM.
Some in France have criticised Mr Netanyahu’s attendance at the commemoration ceremony arguing it was becoming too politicised.
Elie Barnavi, a former Israeli ambassador to France, told AFP news agency: “The presence of Netanyahu makes me a little uneasy.
“This story has nothing to do with Israel.”
The Union of French Jews for Peace (UJFP), a pro-Palestinian organisation, described the decision to invite Mr Netanyahu as “shocking” and “unacceptable”.
However, France’s best-known association of Jewish groups, CRIF, took part in the event.
Mr Netanyahu’s last official visit to France was to attend the unity march following the attacks on satirical magazine Charlie Hebdo, police officers, and a kosher supermarket in January 2015.
After Sunday’s ceremony, he held talks with Mr Macron, where commentators said he would be probing his French counterpart’s intentions towards the Middle East peace process.
When Mr Macron met Palestinian leader Mahmoud Abbas in Paris earlier this month, he reiterated France’s support for a two-state solution and opposition to Israel’s building of settlements in occupied territory.
The meeting with Mr Netanyahu comes amid concerns of another increase in violence in the Israel-Palestinian conflict.
Two Israeli policemen were killed and a third wounded by three Israeli Arabs in a gun attack close to the compound in Jerusalem known to Jews as the Temple Mount and to Muslims as Haram al-Sharif on Friday. The attackers were later killed by security forces.
The holy site was closed after shooting but it reopened on Sunday.