Putin will join Western leaders in celebrating the 70th anniversary of the D-Day landings in France next month despite a standoff over Ukraine, Russia's envoy to Paris said on Thursday.

"French president Francois Hollande has invited Putin who has accepted the invitation and will attend the June 6 ceremony in Normandy," Moscow's ambassador Alexander Orlov told news channel BFMTV on the sidelines of "Victory in Europe" Day ceremony in Paris.

Despite Moscow's calls for postponing the referendum in eastern Ukraine, the leaders of pro-Russia forces ignored the appeal and decided Thursday to move ahead with their plan to hold a referendum on May 11 on the region's future destiny.

"The referendum is the only way to solve the controversial issues and to inform the world of what is really going on here," pro-Russia movement leader Denis Pushilin told reporters during a media conference.

According to him, the working groups of the self-proclaimed republics in the country's Donetsk and Lugansk regions voted unanimously in favor of holding the referendum on Sunday.

The vote, initiated by the pro-Moscow movement in eastern Ukraine, will ask people whether their regions should become sovereign republics, independent from government in Kiev.

At least one person was killed and two others were wounded in a shooting early Thursday near a checkpoint in eastern Ukraine, authorities said.

It was not immediately clear whether the incident has any relation to the pro-Russian movement in eastern Ukraine.