Updated

As two of the most tense regions in eastern Ukraine prepare to vote on declaring sovereignty, the country's acting president is warning them against self-destruction.

The Sunday ballots seek approval for declaring so-called sovereign people's republics in the Donetsk and Luhansk regions, where pro-Russia insurgents have seized government buildings and clashed with police and Ukrainian troops.

At least seven people died Friday in clashes in the city of Mariupol. The city remained on edge Saturday, with barricades of tires blocking some streets in the city center.

President Oleksandr Turchynov, in comments posted on the presidential website Saturday, said supporters of independence for the east "don't understand that this would be a complete destruction of the economy, social programs and general life for the majority of the population."