KIEV, Nov. 21 – Protesting small business owners gave President Viktor Yanukovych time until late Monday to veto controversial new tax legislation and otherwise threatened political action that would seek to dismiss him.

The ultimatum marks an escalation of standoff between thousands of protesters and the government, whose tax legislation cuts taxes on corporations but increases pressure on small businesses.

“Unless Viktor Yanukovych vetoes the Tax Code, we begin procedure of calling a referendum on early termination of President Yanukovych’s authority,” Oleksandr Danyliuk, the leader of the protesters, said Saturday.

Parliament, which is dominated by Yanukovych’s supporters that have voted Friday to approve the Tax Code, will now face the action with protesters campaigning for the referendum to end its authority.

“They failed to meet our ultimatum,” Danyliuk said.

The escalation of tensions comes on the same day that the Orange Revolution, a popular uprising against election fraud in Ukraine, had started exactly six years ago.

The uprising, which began with thousands of people from various regions of Ukraine flocking to Maydan Nezalezhnosti, a downtown square in Kiev, catapulted to presidency then opposition leader Viktor Yushchenko in December 2004.

In apparent attempt to repeat that scenario, the small business owners appealed to the people across Ukraine to join them at the rally at Maydan Nezalezhnosti on Monday.

“We have to clearly understand that if this action fails, there will be no other actions,” Danyliuk said. “Today this is not only an economic and social issue, this is the issue of rights and liberties in general.”

The protesters also called on Ukrainians living overseas to join the protest at Ukrainian embassies and consular offices to raise the international profile of the action.