French members of parliament voted unanimously Friday to criminalise the denial of all crimes against humanity, including failure to admit that the mass killings of Armenians by Ottoman forces was a "genocide".
The amendment, passed on the first reading, sets out penalties of up to a year in prison and a 45,000-euro ($50,000) fine for those who fall foul of the new law, which is expected to raise hackles in Turkey.
Last month, the German parliament voted to recognise the World War I-era killings of Armenians by Ottoman forces as a "genocide", damaging ties between Berlin and Ankara.
Pope Francis also drew Ankara's ire by denouncing the "genocide" during a visit to Armenia -- using a term Turkey rejects for the century-old slaughter.
Ankara argues the killings were a collective tragedy in which both Turks and Armenians died.
The French amendment, which must now go to the upper house Senate for approval, was a promise by President Francois Hollande during his 2012 electoral campaign.
An earlier law against Armenian Genocide denial was struck down by the country's constitutional court for obstructing freedom of speech.
The new legal project covers all events which French law deems to be genocide, crimes against humanity, war crimes or slavery.
Currently, French law only bans Holocaust denial.
"This text will punish the challenge or the trivialisation of all crimes against humanity and war crimes," said Ericka Bareigts, the junior minister in charge of equality.
She said that included the 1915-1917 killings that Armenians say wiped out some 1.5 million of their people.
"This is one of the greatest days of my political career," enthused Henri Jibrayel, a member of parliament whose ancestors survived the mass killings a hundred years ago.
The new law's backers hope to see it enter into force before the end of the year.