Ukrainian Deputy Prime Minister Pavlo Rozenko said on Tuesday that the government's computer network was down, and posted a picture on Twitter of a computer screen showing an error message.
Ukrainian institutions were hit by a wave of cyber attacks earlier in the day, including banks, the state energy distributor and Kiev's main airport.
"We also have a network 'down'," Rozenko said on Facebook. "This image is being displayed by all computers of the government," he said.