Ukraine (BBN)-The US has imposed sanctions against separatists in eastern Ukraine, as the crisis there shows no sign of easing.
The sanctions include asset freezes against seven pro-Russian leaders, reports BBC.
The move was announced as Western leaders threatened additional sanctions against Russia, which they accuse of stoking tension in Ukraine.
Both Russian and the separatists have rejected a unilateral ceasefire called by Ukrainian leader Petro Poroshenko, amid discussion of a peace plan.
'SCALPEL SANCTIONS'
The US and European Union (EU) leaders have previously imposed sanctions after Russia annexed the Ukrainian region of Crimea in March.
On Friday, the US Treasury Department said it had blacklisted seven rebel leaders, including self-proclaimed mayors, governors and commanders in chief of cities under siege by Ukrainian forces.
Their assets in the US will be frozen and US firms will be banned from dealing with them.
Pro-Russian troops prepare to travel in a tank on a road near the town of Yanakiyevo, Donetsk region, eastern Ukraine, Friday, June 20, 2014.
US officials also said "scalpel" sanctions against Russia's defence, finance and high-tech industries were being considered.
US President Barack Obama had spoken separately to French President Francois Hollande and German Chancellor Angela Merkel, a White House statement said.
The leaders had agreed the US and EU would "co-ordinate additional steps to impose costs on Russia" if Moscow did not try to "de-escalate the situation in eastern Ukraine", the statement added.
The US says Russia is providing the separatists with military equipment, including tanks, and is building up troops on its border with Ukraine.
Moscow has denied sending tanks or backing pro-Russian militants.
TRUCE
On Friday, Poroshenko declared a week-long ceasefire to give rebels time to disarm.
He has also unveiled proposals for a peace plan involving decentralising power, holding early elections, and creating a 10km (six-mile) buffer zone on the Ukrainian-Russian border.
However, correspondents say pro-Russian insurgents show no sign of laying down their arms.
A senior rebel commander told Ukrainian news agencies the insurgents would not disarm until government troops had left the east.
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Daniel Sandford reports: ''President Poroshenko announced that his forces, which had been gaining ground, will now cease fire for a week''
The Kremlin dismissed the truce, saying it was "not an invitation to peace and negotiations but an ultimatum".
Tensions in Ukraine rose after former President Viktor Yanukovych refused to sign a trade agreement with the EU in November 2013.
The move sparked huge protests that led to Mr Yanukovych being ousted.
Russia reacted by annexing the Ukrainian region of Crimea, and separatists have occupied parts of eastern Ukraine, where pro-Russian sentiment is strong.
BBN/SS-21June14-11:40am (BST)
