Ukrainian militants blamed for attack on Mariupol

Western states are to discuss tightening sanctions on Russia after Moscow-backed militants were blamed for a rocket attack on the Ukrainian city of Mariupol that killed 30 civilians and injured scores more.

Hours after Saturday's missile strike on the strategic port city, Donetsk separatist leader Alexander Zakharchenko declared that "today, the attack on Mariupol began", before later denying his forces had launched the deadly rockets.

Monitors from the Organisation for Security and Co-operation said the angle of the missile strike showed they were launched from rebel-held territory. This prompted Ukraine, the United States and European Union to demand Russia finally reins in insurgents.

Russian backing

"We are deeply concerned about the latest break in the ceasefire and the aggression that these separatists – with Russian backing, Russian equipment, Russian financing, Russian training and Russian troops – are conducting," US president Barack Obama said. "We will continue. . . to ratchet up the pressure on Russia. And I will look at all additional options that are available to us, short of military confrontation, and try to address this issue."

The White House said US vice-president Joe Biden told Ukrainian president Petro Poroshenko Washington would "work with international partners to ensure that the costs continue to rise on Russia for its aggressive actions against Ukraine".

The EU called an emergency meeting of foreign ministers for Thursday to discuss Ukraine’s conflict, which has killed more than 5,000, displaced one million and is again on a downward, bloody spiral. Diplomatic efforts to revive last September’s Minsk ceasefire deal have failed.

Spilt in opinion

The EU has been split on how to punish Russia, with Poland and the Baltic states among those backing tougher action, and Italy, Hungary, Bulgaria and the Czech Republic opposing tighter sanctions.

"Once again, appeasement encourages the aggressor to greater acts of violence. Time to step up our policy based on cold facts, not illusions," said Donald Tusk, the former Polish premier. Edgars Rinkevics, the foreign minister of Latvia – which holds the EU presidency – wrote on Twitter: "Separatists attack on Mariupol breached Minsk agreements. Russia fully responsible to stop them, if not more isolation & sanctions to come."

Moscow denies sending arms or troops to Ukraine, but has not explained high-tech Russian weapons in rebel hands, the death of its soldiers in Ukraine, or its failure to close its border with rebel-held areas. Russia blocked a UN Security Council resolution condemning the Mariupol attack because, its diplomats said, Britain wanted the declaration to include criticism of the insurgents.