US Secretary of State John Kerry has warned that Russia should “let Ukraine vote” on May 25 or face more targeted economic sanctions.

US Secretary of State John Kerry has warned that Russia should “let Ukraine vote” on May 25 or face more targeted economic sanctions.

"If Russia or its proxies disrupt the [Ukrainian presidential] elections, stand in the way of the Ukrainian people being able to exercise their vote, that is when and if there would be additional sanctions," said Kerry after a meeting in London with foreign ministers from allied European countries on Thursday.

“I'm not going to get into announcing today what the sanctions are," Kerry said. "We have completed our work. We know what they are. ... If they have to go into effect, they will have an impact."

"Let me emphasize, our hope is not to do this," Kerry said "Our hope is not that we have to go to the next stage. I say to the Russians and everybody, our hope is to de-escalate."

Washington shared its strategy to use a "scalpel rather than a hammer" to target vulnerabilities in Russia's business, banking, mining, energy, defense or other sectors, The Associated Press reported, citing a senior State Department official.

Kerry also hailed European-backed talks held in Kiev on Wednesday to end Ukraine’s crisis. The so-called “road map” put forth by the Organization for Security and Cooperation in Europe calling for national dialogue, but pro-Russia protesters were not invited to the session.