"We must learn from the experience of Ukraine, our partners, to prevent deception by Russia," Zelenskyy said in a statement posted to social media.

Whether the U.S.-Russia summit can lead to a deal to produce peace in Ukraine more than 3 1/2 years after Moscow’s invasion remains to be seen.

Small bands of Russian soldiers thrust deeper into eastern Ukraine on Tuesday ahead of a summit this week between Russian President Vladimir Putin and U.S. President Donald Trump, which European Union states fear could end in peace terms imposed on an unlawfully shrunken Ukraine.