KIEV (AFP) - Protesters in Kiev on Sunday vacated city hall after occupying the building for over two months as part of anti-government unrest sweeping Ukraine, in a highly symbolic concession ahead of a new mass protest.
The building in Kiev's city centre had become the "headquarters of the revolution" since December when protesters trying to oust President Viktor Yanukovych stormed and occupied it, and the evacuation comes after authorities also made concessions by releasing people detained in the unrest.
But the opposition has nevertheless warned that nothing short of Mr Yanukovych's resignation will ultimately satisfy protesters.
After the protesters quit city hall, the Swiss ambassador in Kiev - whose country currently holds the rotating presidency of the Organisation for Security and Cooperation in Europe, of which Ukraine is a member - entered the building.
"Switzerland... was invited by both conflicting parties to participate in the process of transferring city hall to authorities," Ambassador Christian Schoenenberger told reporters.
The move comes just hours ahead of a new mass demonstration on Kiev's central Independence Square, which has become a sprawling, anti-government tent city barricaded off on all sides from riot police.
The protest, which kicks off at 1000 GMT (6pm Singapore time), is the 11th since demonstrators first rose up against Mr Yanukovych in November when he rejected a key EU pact in favour of closer ties with Russia.
And while the opposition had promised to prepare a mysterious "peaceful offensive" at the rally as negotiations with the government stalled, authorities yielded some ground on Friday, announcing they had freed all 234 protesters detained in the movement.
But they emphasised that charges against them would only be dropped if conditions of a recent amnesty law were met - which included the evacuation of city hall by Monday.
Some protesters have been charged with fomenting mass unrest, which carries sentences of up to 15 years in jail.
Mr Yanukovych approved the law at the beginning of February after protests in Kiev turned deadly, shocking the country and prompting the shaken president to start negotiating with the opposition.
But protesters were still occupying other public buildings on Sunday as well as Independence Square.
In a Saturday interview with weekly Dzerkalo Tyzhnia, jailed opposition icon Yulia Tymoshenko emphasised that "the only subject of negotiation with Yanukovych is the conditions of his departure."
She accused Mr Yanukovych of having become a puppet of Russian President Vladimir Putin, saying Ukraine had lost the independence it gained from the Soviet Union in 1991.
"Our European friends believe that after long negotiations and loans they can bring Yanukovych back onto the European road," said the former prime minister, who was jailed in 2011.
"They will not be able to do that. Because it's not Yanukovych who decides, but Putin."
Mr Andreas Umland, a political scientist at Kyiv-Mohyla Academy in the Ukrainian capital, said the government and opposition were thought to be negotiating a form of power-sharing agreement to be implemented before early presidential elections were held.
"For now the main question is whether Yanukovych will agree to power-sharing, what kind of power-sharing and how much power will be left to the office of the president," he said.
Like other occupied buildings, city hall had been run with military precision, housing 600 to 700 protesters who slept there to escape the cold and also gathered for meetings, English lessons and other activities.
They had decorated the walls with scores of their own photos and satirical pictures, but the occupation was otherwise clean and orderly, with volunteers working in the kitchen, doling out medicine at a makeshift pharmacy or seeing patients.