Ukraine's government has survived a stormy parliamentary session, in which opposition forces, including heavyweight boxer Vitali Klitschko, were unable to prevail in a no-confidence vote.

Having failed with the parliamentary method, the main opposition leaders said they would blockade the presidential administration and other government buildings until President Viktor Yanukovych dismissed the government and called early elections.

Meanwhile, Yanukovych left Kiev for China on Tuesday, leaving his prime minister, Mykola Azarov, to face the opposition MPs in parliament, which was surrounded by around 10,000 protesters singing and chanting for change – a chorus audible inside the parliament building. Thousands of riot police squared up to the protesters outside to prevent any attempt to storm the building.

Inside, the mood was no less emotional. Azarov was heckled throughout the duration of a speech in which he apologised for police violence against protesters on Sunday but showed no intention of resigning and even threatened the opposition movement with renewed force if it did not back down.

Ukraine's prime minister, Mykola Azarov. Photograph: Efrem Lukatsky/AP

"We are open for dialogue," he said. "We have extended our hand to you, but if we encounter a fist, I will be frank, we have enough force."

Azarov, who hails from Yanukovych's heartland in the Russian-speaking east of the country, and does not speak Ukrainian, addressed the parliament in Russian but was drowned out by chants of "Speak Ukrainian!" and "Resign!" by nationalist MPs. Undeterred and at times inaudible, Azarov soldiered on. In a no-confidence vote at the end of the session, support from Yanukovych's Party of Regions was enough to keep the government in place.

Yanukovych has been under pressure since he announced last week that the government was abandoning negotiations on an association agreement with the EU in favour of closer relations with Russia. He says Ukraine's dire economic situation means his hand was forced, and that the country is still on the path towards Europe in the long term. His opponents, however, have reacted furiously, taking to the streets on Sunday in the biggest protests since the 2004 Orange Revolution.

"No decisions taken under pressure and populist rhetoric can be good ones," said the Party of Regions MP Anatoliy Kinakh, who accused the protesters of endangering the stability of the country and worsening its already fragile economy. He denied that Yanukovych's decision to leave the country was ill-judged. "It is an official visit to one of our strategic partners and has been planned for six months," he said. "It was important for the president to go."

As Yanukovych has kept his head down, the protests have taken a distinctly personal bent. Opposition leaders, including Klitschko and the party of jailed former prime minister Yulia Tymoshenko, want early parliamentary and presidential elections.

Rostyslav Pavlenko, an MP from Klitschko's Udar party, said that nothing short of the resignation of the government and the president himself would satisfy protesters.

"We will block administrative buildings and call a general strike until we achieve this," he said. "We can make the country literally stop working," .

Police have abandoned Independence square, which had been been surrounded by makeshift barricades, and yet with the government unwilling to compromise, it is difficult to see how the impasse will be broken.

Away from the streets, the invisible decisions taken by Yanukovych's oligarchic backers will prove crucial. Taras Chornovil, a former MP from Yanukovych's party who led his 2004 presidential campaign, said that factions inside the Rada are controlled by different oligarchs and these poweful players are yet to decide whether to ditch the president or keep faith with him.

"Some of the MPs inside the Party of Regions are not dependent on the party leaders but on other influential people," he told the Guardian. "Everything may change depending on what the main sponsors of the party decide. Ukraine's fate is not decided on Independence Square, or in the parliament, but somewhere in Monaco. The richest and most influential people are now making their decision."