EU warns Russia of new sanctions over Ukraine militants
The EU says it is ready to impose new sanctions on Russia if Moscow does not act quickly to stop arms and militants flowing into eastern Ukraine.
UK Foreign Secretary William Hague warned Russia that if it failed to act the EU "will be able to take further measures, further sanctions".
He said Russian President Vladimir Putin's support for Ukraine's peace plan must be "translated into action".
Ukraine says armed pro-Russia militants are ignoring Kiev's unilateral truce.
On Friday Ukrainian President Petro Poroshenko announced a 15-point peace plan and declared a unilateral week-long truce.
President Putin welcomed the move, but said Kiev must negotiate and make compromises with the pro-Russian rebels, who remain in control of key state buildings in eastern Ukraine.
EU foreign ministers are discussing the Ukraine crisis in Luxembourg with the new Ukrainian Foreign Minister, Pavlo Klimkin.
The crisis will also be high on the agenda of an EU summit in Brussels on Friday, where EU leaders could announce further sanctions against Russia if they deem Moscow's response to the peace plan to be inadequate.
Western leaders accuse Russia of arming the anti-Kiev militants in Donetsk and Luhansk, where ties with Russia are traditionally strong.
Friday will also see the signing of a key EU-Ukraine association agreement - a far-reaching partnership deal which lies at the origin of the Ukraine crisis.
The refusal of former Ukrainian President Viktor Yanukovych to sign the agreement last November, under heavy Russian pressure, triggered massive pro-EU street protests which forced him out of office.
So far the EU and US have imposed visa bans and asset freezes on Russian officials accused of involvement in the Ukrainian unrest, including Russia's annexation of Crimea.
But so-called "Phase Three" sanctions would mean wider economic measures denying Russian access to certain technologies and investments.
"Those measures are ready to take," Mr Hague warned on Monday.
"We look to Russia to take actual action to stop the flow of arms over the border into eastern Ukraine, to encourage illegal armed groups to stop what they are doing there now.''
Sweden's Foreign Minister Carl Bildt said Russia had been "issuing all sorts of threats of trade action" against Ukraine over Kiev's plan to sign the association agreement.
He also complained that Russia "is conducting a propaganda war with full speed ahead and no signs of them closing the border" to stop arms and militants entering Ukraine.
The political part of the association agreement was signed in March, and the EU plans to fast-track free trade provisions so that Ukraine can get a much-needed economic boost as early as this autumn.
President Poroshenko's peace plan involves decentralising power, holding early elections, and creating a 10km (six-mile) buffer zone on the Ukrainian-Russian border.
But rebel leaders say they will not disarm until government troops have left the east.
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