Russia blocks U.N. statement on Ukraine as fighting escalates

UNITED NATIONS (Reuters) - Russia prevented the U.N. Security Council on Saturday from criticizing statements by pro-Russian Ukrainian rebels and condemning an upsurge in violence that has claimed dozens of lives in Ukraine, council diplomats said.

Pro-Russian rebels have launched an offensive against the strategic port of Mariupol in eastern Ukraine, prompting warnings from the European Union and U.N. Secretary-General Ban Ki-moon.