The European Union has imposed its first sanctions against Ukraine, joining the United States in a two-pronged campaign of public pressure and backroom diplomacy against the Russian-backed Government in Kiev.
President Viktor Yanukovych last night claimed he had reached a deal with the opposition to end the crisis after all-night talks mediated by EU foreign ministers.
His website said the deal would be signed later but the opposition had not confirmed the claim.
But earlier in the day the 28 EU nations, incensed by the lethal crackdown on protesters demanding the ousting of Yanukovych, agreed to impose an asset freeze and travel ban against key members of the regime. The measures will apply to those "with blood on their hands", Italian Foreign Minister Emma Bonino told journalists in Brussels. Work on drawing up the list was due to begin overnight.
Ministers also agreed to suspend the export of anti-riot equipment to Ukraine, and to offer medical assistance and visas to dissidents and to those injured.
That statement, issued as EU envoys met the embattled President, reiterates EU calls for constitutional reform and the formation of a new government ahead of the organisation of free and fair elections.
The measures highlight the hardening mood in the EU, an important trade partner with Ukraine, and a closer alignment with Washington in a crisis that has placed the West on a collision course with Moscow.
Scores have been killed this week in battles in Kiev between demonstrators and security forces.
Yanukovych says he is battling an insurrection and describes the protests as an attempted coup.
"By permitting such actions to take place, the Ukrainian Government is putting itself at odds with reasonable opinion all across the world," Britain's William Hague said. "It is not right to describe protesters as terrorists. A great many of them are simply seeking a better future for their country."
The White House put 20 top Ukrainian officials on a blacklist as a first step towards a wider roster of sanctions.
The deeply controversial figure at the centre of it all is Yanukovych, a pro-Russian conservative whose alleged rigging of elections in 2004 triggered Ukraine's "Orange Revolution" - a convulsion that led to more turbulence and political fraud rather than a stable democracy.
The country is now ripped in two between its western Ukrainian-speaking half, whose public is clamouring for Ukraine to join the EU, and its eastern Russian-speaking half, which sees Moscow as its natural ally.
Desperate to keep Ukraine within its sphere of influence, Russia offered Yanukovych a US$15 billion ($18.1 billion) economic lifeline and a 30 per cent cut in the price of imported Russian gas in exchange for ditching a trade and political pact with the EU.
Russian Foreign Minister Sergei Lavrov blasted sanctions as "bullying" and slapped down the protesters as "extremists and hardliners who are trying to provoke a civil war".
Even though the EU sanctions mark an about-turn, the toughening is limited, and the main hope lies with a political solution.
Foreign ministers from France, Germany and Poland met with Yanukovych and the three main leaders of the opposition, hoping to unlock a deal on a truce followed by early elections.
At the same time, German Chancellor Angela Merkel, US President Barack Obama and Russian President Vladimir Putin jointly called for "a political solution".
According to official figures, the EU accounts for about 30 per cent of Ukraine's trade. In 2009 the EU launched its Eastern Partnership aimed at deepening relations between the EU and six neighbouring former Soviet bloc countries.
The EU provides Ukraine with technical and financial assistance in some 400 programmes to promote good governance, sustainable development, infrastructure improvement and healthcare. EU aid to Ukraine between 2011 and 2013 was 470 million ($775 million).