Ukraine's parliament voted on Tuesday for the country to renounce its "nonaligned" status and work towards membership in the NATO alliance.
The amendment received 303 votes, 77 more than the minimum required to pass into law.
The move will be seen is an unfriendly step towards Russia and will only "add to nuisances" in ties, Russia's envoy to the Organisation for Security and Cooperation in Europe said on Tuesday.
"It's an unfriendly step towards us. This political vector will only add to nuisances and acuteness in ties," news agency Interfax cited diplomat Andrei Kelin as saying.
Follow us on Twitter: @CNBCWorld