Ukrainian President Viktor Yanukovych to return to work

Ukrainian President Viktor Yanukovych is to return to work on Monday after four days of illness, with protesters still demanding he give up power.

The political crisis has continued unabated in his absence, with thousands on the streets of the capital, Kiev.

Meanwhile, opposition leader Dmytro Bulatov has arrived in Lithuania for medical treatment.

Mr Bulatov appeared on TV last week saying he had been abducted and tortured.

Mr Yanukovych has not been seen in public since last Wednesday. His office says he had been suffering from a fever and breathing problems but that he was feeling well again and will go back to work.

Opposition leaders had previously expressed scepticism about his illness - on Sunday they again called on him to stand down while speaking to crowds of protesters in Kiev's Maidan square, the BBC's Duncan Crawford reports from the capital.

Thousands are currently in the square, which has become a focal point for the opposition.

Mr Yanukovych has offered a number of concessions and his cabinet quit their jobs.

But the demonstrators, many of whom want to see closer ties with the EU rather than Russia, have not been placated.

Mr Bulatov arrived in Vilnius in the early hours of Monday morning and was immediately taken to hospital, the Baltic News Service reports.

Lithuania has promised to treat any protesters injured in the crisis.

He went missing on 22 January and re-emerged eight days later on the outskirts of Kiev.

He appeared on TV with a gash on his face and part of his ear cut off. He said he had been held and beaten for eight days.

His case became a new rallying point for anti-government protesters.

Mr Bulatov was a leader of a group called AutoMaidan, made up mainly of drivers who would protect the protest camps and blockade streets.

He told the media he had been "crucified" by his abductors, whom he could not identify other than to say they had Russian accents.

Opposition politicians and Western diplomats expressed outrage at the incident.

EU foreign policy chief Catherine Ashton condemned the "deliberate targeting of organisers and participants of peaceful protests".

Officials had suggested Mr Bulatov's account of the abduction might have been fabricated.

"The only thing he has is a scratch on one of his cheeks," Foreign Minister Leonid Kozhara told broadcaster al-Jazeera.

"It looks like the alleged story that he was kidnapped and tortured is not absolutely true."

The ministry later said the comments did not reflect his "real attitude to the tragic situation", and said the minister wished Mr Bulatov a speedy recovery.