Ukrainian opposition protesters were in full control of this capital on Saturday after President Viktor Yanukovych left for his political base in the country's east, while parliament ordered the release from prison of his chief rival, former Prime Minister Yulia Tymoshenko.

The Maidan self-defense forces, the anti-Yanukovych popular protest movement that until Friday had spearheaded fighting against security forces in Kiev, were sharing the task of guarding the presidential palace, parliament and other government buildings with police, who were now siding with the pro-Europe opposition.

The presidential residence, located in a Kiev suburb, was also being guarded by the Maidan.

These latest developments follow Friday's signing of a deal between opposition leaders and Yanukovych, who agreed to call early presidential elections in a bid to put an end to bloody street battles that left dozens dead this week in Kiev.

The head of state also pledged to revert to the previous 2004 constitution, which gave the president fewer powers, and said he would start the process of forming a coalition government.

Shortly after the deal was signed, Ukraine's parliament approved a resolution to "comply with its international commitments" and free Tymoshenko, who had been imprisoned on abuse of power charges related to a natural gas deal with Russia.

The lawmakers voted to decriminalize sections of Ukraine's criminal code under which she was imprisoned; she is currently being held at a hospital in the eastern city of Kharkiv.

The parliament also elected a close ally of Tymoshenko's as its new speaker.

Yanukovych, meanwhile, has traveled to the eastern city of Kharkiv after departing Kiev, lawmaker and advisor to the head of state Anna Guerman told the local UNN news agency, adding that the president would address the nation from that city on Saturday.

She was seeking to quash rumors, which were even being spread in parliament, that Yanukovych had fled the country.

The president, meanwhile, said Saturday in an interview with the UBR television network that the latest developments in the country amount to an attempted coup but vowed not to step down.

In Russian-speaking Kharkiv, a stronghold of Yanukovych's Party of Regions, a congress of deputies from eastern Ukraine and the Crimea urged citizens in those regions to organize to resist the Maidan.

Disturbances in Kiev this week left 80 people dead, according to the latest official figures, although opposition groups say that nearly 100 people were killed on Thursday alone, when a truce agreed the previous night was shattered by clashes in the capital's downtown Independence Square.

In the wake of the violence, urgent round-the-clock negotiations mediated by European foreign ministers were held that led to the deal signed on Friday.

Ukraine's crisis erupted at the end of November, when Yanukovych backed away from plans to ink a pact with the European Union and instead signed a $15 billion financial-aid package with Russia.

Protesters took to the streets of Kiev and began occupying administrative buildings, prompting Ukraine's parliament, then controlled by Yanukovych's allies, to pass a package of laws on Jan. 16 restricting freedom of assembly, freedom of speech and other basic rights.

Violent clashes pitting demonstrators and riot police broke out three days later and left six dead and hundreds wounded.

Ukrainian officials and opposition leaders began seeking a negotiated solution to the crisis in the wake of the bloodshed.

The talks led to the resignation of Prime Minister Mykola Azarov and the repeal of the controversial anti-protest laws, but opposition demonstrators have continued to demand that Yanukovych also step down. EFE