French President Francois Hollande on Sunday denounced separatist votes by pro-Russian rebels in eastern Ukraine as "null and void".
On a visit to the ex-Soviet republic of Azerbaijan, Hollande said the votes taking place in Donetsk and Lugansk made "no sense" and that only Ukraine's presidential vote on May 25 mattered.
"I don't want to call them referendums," Hollande said, adding they "had no legitimacy and no legality".
"What will count in my eyes, the only election that matters, is the one on May 25, the election that will allow for the naming of a president for all of Ukraine," Hollande said.
"It is with that president -- who will be the only legitimate one -- that it will be possible to consult with all stakeholders and then allow for a revision of the Ukrainian Constitution, the treatment of minorities, decentralisation."
He reiterated that if the presidential election does not take place "it will be necessary to move on to another level of sanctions".
"But today I would bet that this election on May 25 will take place."