The Kremlin on Friday offered to "explain" Moscow's actions in Ukraine to French actor Gerard Depardieu after he denounced Russian President Vladimir Putin's "crazy, unacceptable excesses".

Depardieu, a long-time star in France before Peter Weir's 1990 film "Green Card" made him a Hollywood celebrity, left France and took up Russian nationality in 2013 to protest against a proposed tax hike on the rich in his homeland.

The 72-year-old became a friend of Putin, but came out against the conflict in Ukraine and called for negotiations just days after the start of Moscow's military campaign in Ukraine.

"I'd suggest that Depardieu most likely does not fully understand what is happening," Kremlin spokesman Dmitry Peskov told reporters.

"He does not understand what happened in Ukraine in 2014," Peskov said, accusing Ukraine of bombarding civilians in the country's east.

Depardieu became friends with Putin
Depardieu became friends with Putin RIA-NOVOSTI via AFP / MIKHAIL KLIMENTYEV

"If necessary, we will be ready to tell him about this and explain so that he understands better," Peskov added.

One Russian lawmaker, Sultan Khamzayev, said the actor should be stripped of Russian citizenship and his property handed over to orphans.

In a statement to AFP on Thursday Depardieu said: "The Russian people are not responsible for the crazy, unacceptable excesses of their leaders like Vladimir Putin."

Putin sent troops to pro-Western Ukraine on February 24, saying Moscow needed to "demilitarise" and "denazify" the ex-Soviet country.

Ties between the two nations were shredded after a pro-Western uprising in Kyiv ousted a Kremlin-backed leader in 2014, and Moscow moved to annex Crimea and supported a pro-Russian insurgency in the east of Ukraine.