Ukraine leader calls 'truce' amid threat of EU sanctions

Ukraine's embattled leader announced a "truce" with the opposition as he prepared for a grilling by visiting EU diplomats today over clashes that killed 26 and left the government facing diplomatic isolation.

US President Barack Obama cautiously welcomed the apparent effort to defuse the crisis as thousands of helmeted protesters steeled themselves for new clashes with riot police on Kiev's flame-engulfed main square.

Ukrainian President Viktor Yanukovych proposed the start of direct talks with the opposition after meeting three top anti-government lawmakers less than a block from the site of the deadliest unrest.

"The sides announced a truce and the start of a negotiations process aimed at ending the bloodshed (and) stabilising the situation in the country for the benefit of civil peace," Yanukovych said in a statement posted after talks that included protest leader Vitali Klitschko.

But the scenes playing out in the heart of Kiev suggested a war zone that was being reinforced from all sides before a new fight following a night of the bloodiest violence in Ukraine's post-Soviet history.

Pungent smoke from car tyres rose over the capital's iconic Independence Square while bursts of gunfire and exploding stun grenades echoed across the paralysed city centre as determined pro-Western protesters faced off against heavily-armed police over burning barricades.

The violence that erupted into apocalyptic scenes Tuesday as police and protesters battled in Kiev's historic centre came after three months of mass protests in Ukraine that have also pitted Russia and the West in an increasingly bitter war of words.

The crisis was initially ignited by Yanukovych's shock decision in November to ditch an historic EU deal in favour of closer ties with Kiev's historic master in the Kremlin. But it has since evolved into a much broader anti-government movement that has swept through both the pro-Western west of the country as well as parts of its more Russified east.

The crackdown on protesters triggered a storm of condemnation from the West while the Kremlin denounced an "attempted coup" by the demonstrators.

The US announced it was imposing visa bans on about 20 senior Ukrainian officials "complicit in or responsible for ordering or otherwise directing human rights abuses."

The Cold War-style confrontation over Ukraine's future gained steam with a string of outraged comments from Moscow that included condemnation of the both protesters and the West.