Western countries have scrambled to find a solution to the crisis rocking Ukraine and save the country from economic collapse as its interim leaders delayed the formation of a new government.
Ukraine has appealed to the West for $US35 billion ($A38.86 billion) in aid to avoid a catastrophic default as the nation tilts away from Russia following the weekend ousting of pro-Moscow president Viktor Yanukovych after days of carnage in Kiev that left almost 100 people dead.
Yanukovych, whose whereabouts are still unknown, has since been hit with an arrest warrant for "mass murder" over the deaths and his entire government has collapsed.
But Ukraine's former masters in the Kremlin have angrily questioned the legitimacy of the new leadership and accused them of leading an "armed mutiny".
The tumultuous events of the weekend capped more than three months of relentless protests against Yanukovych's rule sparked by his November decision to spurn an historic pact with the European Union in favour of closer ties with Russia.
The country of 46 million people is now in urgent need of a interim government to guide the country to stability ahead of a presidential election set for May 25.
But the much-anticipated announcement of a new cabinet and prime minister was on Tuesday delayed until Thursday.
EU foreign policy chief Catherine Ashton arrived in Kiev on Monday as the Ukrainian capital slowly returned to normal, with shops and restaurants in the centre reopening.
She is due to brief the press Tuesday after meeting interim leader Oleksandr Turchynov, although the European Union has voiced caution about Ukraine's prospects of membership.
Turchynov has warned that Kiev will have no alternative but to default on $13 billion in foreign obligations due this year should the West fail to come to the aid of the economically-struggling country.
Adding to the diplomatic effort, Washington is sending Deputy Secretary of State William Burns to Kiev Tuesday.
British Foreign Secretary William Hague is also in Washington for talks with US Secretary of State John Kerry and the IMF and is due to visit Ukraine soon.
He said the IMF was "best placed" to provide immediate financial and technical support but stressed that aid would be dependent on economic and political reforms.
While Western powers have cautiously thrown their weight behind the overthrow of democratically-elected Yanukovych, Russia has reacted with outrage to the "mutiny" in a country with centuries-old roots to Moscow.
The United States has stopped short of endorsing Ukraine's interim leader and called for a technocratic government to promote early elections.
The whereabouts of Yanukovych, meanwhile, remained unknown.
Acting interior minister Arsen Avakov said he had tried to flee the country Saturday out of the eastern city of Donetsk - his political power base and bastion of pro-Russian support - before escaping to Crimea, a base of Russia's Black Sea fleet, with a team of guards and a cache of weapons the next day.
