Electricity supply to Crimea has been reduced by half and the region is experiencing rotating blackouts following two accidents on power lines coming from Ukraine, Crimea’s energy company says.

Earlier, Crimean Vice-PM Rustam Temirgaliev said that Ukrainian national energy company Ukrenergo reduced the electricity supply to Crimea by 50 percent. “Ukrenegro reduced the power in its power lines cutting the amount of supplied energy by half,” the top official told Kryminfo news agency.

Temirgaliev described the power shortages as “blackmail” on behalf of Kiev.

Crimean energy company DTEK Krymenergo said in a statement on its website that accidents on two power lines connecting the peninsula with Ukraine forced it to put them offline on Sunday.

There are a total of three power lines coming from Ukraine. All of them are operated by Ukrenergo.

This comes after Crimea and the port city of Sevastopol officially joined Russia after President Vladimir Putin signed law amending the Russian constitution to reflect the transition on Friday. Earlier, Russian lawmakers ratified both the amendment and an international treaty with Crimea and Sevastopol, which was legally required for the incorporation.

The Russian ruble becomes an official currency of the peninsula on Monday, alongside the Ukrainian hryvnia.

Temirgaliev also said earlier the reduction of the energy supply is Kiev’s attempt to blackmail the Russian Federation into some concessions. “It can be explained by these people’s foolishness,” he said. “We don’t have any debts. There is no reason for the blackout. They are just ‘training.’”

The vice-PM added that Crimea was prepared for such developments. “We understand what we are signing up for. We will economize on consumption, but we won't have any disaster, crisis or collapse.”