Anti-government protesters have beefed up barricades in Ukrainian capital Kiev ahead of a new mass rally, defying President Viktor Yanukovych after he approved strict curbs on rallies in a move that provoked an outcry in the West.

Sergey Kaplin, a lawmaker from opposition UDAR party, said on Saturday the opposition has begun preparing for a nationwide strike for the next day.

We are returning to Stalinism. When these laws are enforced the situation in Ukraine will be worse than in Russia or Belarus. Leonid Tertichny, protester in Kiev

Yanukovych, who has been wrestling with nearly two months of opposition protests, signed off on Friday on tough new laws introducing jail time and corrective labour for those occupying public buildings or disseminating slander on the Internet.

But the curbs are expected to reinvigorate the pro-EU opposition movement.

"We are returning to Stalinism. When these laws are enforced the situation in Ukraine will be worse than in Russia or Belarus," Leonid Tertichny from the central Cherkasy region said at the protest camp.

"But these laws have not intimidated us, they mobilised people. The protests will continue."

Olena Oshchepovska, a protester, said the new laws showed the government was afraid of its own people.

Several dozen pro-government demonstrators on Saturday attempted to hold a rally near the protest camp but were chased away. The opposition accused the government supporters of trying to provoke fresh scuffles.

Jailed opposition leader Yulia Tymoshenko accused her arch-rival Yanukovych of seeking to establish a "neo-dictatorship", urging people to mount a strong response.

In a fresh sign of mounting tensions, the president on Friday evening dismissed Sergiy Lyovochkin, his chief of staff, and will skip this week's economic forum in the Swiss ski resort of Davos.

The ex-Soviet country will be represented at the prestigious forum by Prime Minister Mykola Azarov.