Ukrainian President Petro Poroshenko on Thursday hailed new sanctions imposed by the European Union (EU) against Russian entities, saying it showed Europe's solidarity with Ukraine.

"The European Council has taken an important step in support of Ukraine's sovereignty, territorial integrity, and independence," Poroshenko said on his official Twitter account.

EU leaders agreed to impose sanctions on Russian companies helping to destabilize Ukraine at a special meeting of the European Council on Wednesday in light of the latest developments in the country.

The sanctions were imposed "with a view to targeting entities, including from the Russian Federation, that are materially or financially supporting actions undermining or threatening Ukraine's sovereignty," said an official statement.

A few hours before Brussels' announcement, the United States also announced the most wide-ranging sanctions yet on Russia, targeting key institutions including Gazprombank and Rosneft, as well as other energy and defense companies.