A majority of Ukrainians back the opposition's demand for early elections but are about evenly split between supporters and opponents of an association agreement with the European Union, a poll found today.

The internet survey by the TNS agency in Kiev found 51.3% of its 1,008 respondents, all town or city residents, favoured bringing President Viktor Yanukovych's term to an end and calling early elections.

The Mr Yanukovych, 63, who was elected in 2010, is only due to step down in 2015.

However, protesters camped out in Kiev and cities across Ukraine are calling for him to resign.

The poll also found that 58% of respondents were in favour of early parliamentary elections.

Asked about possible prime ministers, the highest proportion -- 21.8%, chose pro-opposition tycoon Petro Poroshenko.

However, 21.6% percent picked interim cabinet chief Sergiy Arbuzov, a Yanukovych loyalist.

Ukraine's previous prime minister, Mykola Azarov, resigned last month along with the entire cabinet in a concession to the opposition following two months of protests.

Showing divisions between Ukrainians on foreign policy, 48% said Ukraine should reconsider its rejection of an EU partnership, but 40.3% said it should not.

Asked if the protests should continue, 48% said yes and 45.1% said no.

Meanwhile, Mr Yanukovych has slammed the protest movement as "extremism" and "radicalism", taking a hard line against the opposition after returning from sick leave.

"We have to say no to the extremism, radicalism and incitement to hatred in society behind which lies a struggle for power," he was quoted as saying in a statement issued by the presidency.

He returned to work today from four days of sick leave after opposition leaders appealed for Western assistance and an injured militant accused of rioting left the country for medical treatment.

"Yes, the president has come back to work," a spokesman said without giving further details on the leader's agenda for the day.

As he recovers from what officials said was an "acute respiratory infection", Mr Yanukovych faces a crisis with no solution in sight.

Opposition leaders have asked the West, which has so far pledged only verbal support for their cause, to mediate in talks with Mr Yanukovych to prevent "misunderstandings".

They have also requested "real financial aid" after more than two months of protests that have left much of central Kiev looking like a war zone and hobbled an already frail economy.

Speaking to a protest rally of over 60,000 people yesterday, former economy minister Arseniy Yatsenyuk said Western officials had assured him that funding was on its way.

"They are ready to do it," he told the crowd.

The case of Dmitry Bulatov showed the international resonance of events in Ukraine after EU and US officials reacted with shock to his account of being kidnapped and tortured.

Bowing to pressure, a Kiev court allowed the 35-year-old to leave the country for treatment in Lithuania and he was quickly taken by ambulance to the airport.

Mr Bulatov said he was "crucified" by his unidentified captors before being released in a forest last week and images of his bloodied face were broadcast around the world.

Ukrainian authorities have cast doubt on the veracity of his story and Foreign Minister Leonid Kozhara dismissed his injuries as "a scratch" before retracting the comment.

The case has been highlighted by the opposition as an example of what it says is a "secret repression" against protesters in which pro-government vigilantes have been employed.

The protests began in November when Mr Yanukovych turned his back on a partnership deal with the European Union under pressure from Russia.

They have since expanded beyond Kiev into traditionally pro-opposition western Ukraine, but also into central and eastern parts normally considered a heartland for Mr Yanukovych.

Four people - two protesters and two policemen - were killed at the height of the clashes last month and more than 500 people have been injured, according to official figures.

Russia has today called on Ukraine's opposition to stop what it called "threats and ultimatums".

"We expect the opposition in Ukraine to renounce threats and ultimatums and revitalise a dialogue with the authorities with a view to taking the country out of a deep crisis and into a constitutional sphere," the foreign ministry said in a statement.