Russia questioned on Saturday the May 25 presidential poll in Ukraine as it slammed Kiev’s military offensive against pro-federalization activists in the ex-Soviet country.

Russia questioned on Saturday the May 25 presidential poll in Ukraine as it slammed Kiev’s military offensive against pro-federalization activists in the ex-Soviet country.

"Can elections held amid the thunder of guns really meet the democratic norms of the electoral process?" the foreign ministry said in a statement.

Moscow also urged authorities in Kiev to "immediately end military operations" in the country's southeast.

Accusing Kiev of carrying out "punitive action against its own citizens," Moscow said Ukrainian  troops had attempted overnight to storm the town of Slavyansk in the Donetsk region, using air support and heavy artillery.

It said people had been wounded in the attack and accused Kiev of "creating a real threat to the lives of civilians".

It also charged that Kiev's pro-Western government was using talks on national reconciliation "as a cover for aggressive action".

It urged Western nations to convince Ukraine's interim leaders to "launch real and not phony work toward national reconciliation".