The European Union (EU) has agreed to widen sanctions against Moscow, as Armed pro-Russian separatists seized more buildings in eastern Ukraine.

At the end of a meeting of European foreign minister on Monday, British Foreign Minister, William Hague, said the ministers agreed to expand a list of Russians barred from travelling or doing business in the EU.

“Work would begin to come up with new names for the sanctions list,” Hague said.

In Washington, White House spokesman, Jay Carney, said President Barak Obama would speak to Russian President, Vladimir Putin, by phone later on Monday. Washington is also planning to expand its sanctions list. Russia has so far shrugged off targeted sanctions.

Armed pro-Russian separatists seized more buildings in eastern Ukraine on Monday, expanding their control after the government failed to follow through on threatened military crackdown leaving Moscow’s partisans essentially unopposed.

Rebels in the town of Slaviansk, where the authorities failed to follow through with their announced “anti-terrorist” operation, called for Russian President Vladimir Putin’s help.

Ukraine’s interim president, Oleksander Turchinov, said the offensive against the rebels would still go ahead. But in a sign of discord behind the scenes in Kiev, he sacked the state security chief in charge of the operation.

In Donetsk, rebels holed up in the administrative headquarters of a province that is home to 10 per cent of Ukraine’s population said they planned to seize control of infrastructure and the levers of state power.

They have declared an independent “People’s Republic of Donetsk” and sought Putin’s protection if they are attacked.

Rebels have also seized buildings in around 10 other towns and cities across other eastern provinces which form the heartland of Ukraine’s heavy industry.

In a bid to undercut the rebels’ demands, Turchinov held out the prospect of a countrywide referendum on the future shape of the Ukrainian state. Pro-Russian secessionists want separate referendums in their regions, which Kiev says is illegal.

The uprising in eastern Ukraine began eight days ago but has accelerated sharply in the past 48 hours, with separatists seizing ever more buildings, including arsenals filled with weapons. They have met little opposition.

Kiev says the separatists are organized by Moscow, seeking to repeat the seizure of the Crimea region, which Moscow occupied and annexed last month.

Russia says the armed men are all locals acting on their own, but Western officials say the uprising is too well-coordinated to be entirely spontaneous, and bears too many similarities to the Russian operation in Crimea.