French parliamentary speaker François de Rugy defended welcoming Andriy Parubiy to the parliament on Monday, judging it "normal that I receive my counterpart, elected in free elections".
But Parubiy is a controversial figure, one of the founders of the right-wing Svoboda party, which was formerly the Social-National Party of Ukraine, whose symbol was a version of a Nazi symbol, the Wolfsangel.
Its virulent anti-communism has evolved into anti-Russian Ukrainian nationalism.
Svoboda limits membership to ethnic Ukrainians and at one time would not accept atheists or former communists.
Although some analysts believe it is moving from the far right to the mainstream, the European parliament in 2012 expressed concern about its "racist, anti-Semitic and xenophobic views".
French hard-left leader Jean-Luc Mélenchon clearly does not believe Svoboda has changed.
He called Parubiy an "anti-Semitic neonazi" in a tweet, commenting about his presence in the National Assembly, "This is where unbridled Atlanticism gets us."
Before the meeting his fellow France Unbowed MP Alexis Corbière called for it to be cancelled because "the French republic has no business honouring a violent xenophobe".
A statement by the Communist-led parliamentary group also condemned the visit, declaring it "incompatible with all the values on which our republic is founded".
Efforts to revive Ukraine-Russia peace talks
De Rugy said he was acting in the spirit of diplomacy and would soon be renewing contact with the Russian Duma.
They were broken off several years ago over Russia's alleged support for rebels in eastern Ukraine and its annexation of the Crimean peninsula.
French Foreign Affairs Minister Jean-Yves Le Drian joined his German, Russian and Ukrainian counterparts in Berlin to try to revive Russia-Ukraine peace talks and a truce agreement that is widely ignored.
Germany's Heiko Maas expressed cautious optimism about the prospects.
Russia's Sergei Lavrov said they had discussed a "road map" for prisoner exchanges.
Le Drian said he saw "a positive dynamic for what I hope will be a peaceful solution", adding that Paris and Berlin had offered to assist in demining operations.
In the long run, he said, "we are ready to work on the parameters of a possible United Nations mission for eastern Ukraine when the implementation of the Minsk agreements will allow it".