The Interior Ministry confirmed the taking over of the Ukrainian House, an exhibition hall used by troops as a base, in central Kiev, saying the forces showed restraint and withdrew to avoid further tension.
Ukraine state television said that around 200 police forces left the building by a side entrance.
“The ministry’s leadership decided to withdraw the reserve unit of security forces from the building,” the ministry said in a statement.
Opposition leader Vitali Klitschko, who was present at the scene, also confirmed the building had been seized.
“The task has been accomplished. The Ukrainian House has been taken without bloodshed,” he said, adding that the protesters do not plan to use the building but will guard it so that police cannot return.
The overnight violence at the building came after opposition leaders promised to keep up protests despite an offer of concessions by President Viktor Yanukovych to end the prolonged crisis.
In a statement released on Saturday on the presidential website, Yanukovych offered the post of the prime minister to Arseny Yatsenyuk, the former economy minister, and the post of deputy prime minister to Klitschko.
He also pledged to change the constitution to reduce the president’s powers.
Ukraine has been rocked by anti-government protests since Yanukovych refrained from signing the Association Agreement with the European Union at the third Eastern Partnership Summit in the Lithuanian capital, Vilnius, on November 29, 2013.
Kiev refused to sign the agreement after EU leaders called on Ukraine to allow jailed opposition leader Yulia Tymoshenko to travel overseas for medical treatment.