KIEV (AFP) -- Ukraine was mired in political crisis Monday ahead of a meeting of the constitutional court this week to rule on President Viktor Yushchenko's bid to force early parliamentary elections.

Around 1,000 protesters remained camped out around parliament building in central Kiev, determined to stop the Western-leaning president's dissolution of the legislature, which is dominated by a pro-Russian coalition.

The situation was calmer on the streets compared to last week's mass demonstrations as Monday was a holiday following the Easter weekend in this Orthodox Christian country.

However, with the constitutional court planning to convene this week for what could be lengthy deliberations on Yushchenko's election plan, tensions were high. "It is my duty to be here," said Andrei Dyadyuk, a member of the Regions Party of Yushchenko's arch-rival, Prime Minister Viktor Yanukovych. "But today there are no demonstrations. We are Orthodox people, and we don't organize public meetings during holidays."

In a combative Easter speech televised late Saturday, Yushchenko accused his opponents of trying to impose "tyranny" and "managed democracy" in Ukraine.

"My decision is legitimate and constitutional and there will be no going back," Yushchenko said in his speech, delivered from outside the Saint Sophia church in central Kiev. His rival Yanukovych also issued an Easter message posted on the government website Sunday in which he expressed confidence that the crisis "will be successfully resolved through democracy and supremacy of the law."

The crisis began April 2 when the president ordered the dissolution of parliament and elections on May 27. This triggered a defiant response from the pro-Russian prime minister. "It's cold on the street but God will keep us warm," pensioner Nina Pustavoytova from Eastern Ukraine said outside the parliament early Monday. "People who believe in God are here to defend their rights."

Critics have accused the president of mounting a coup by illegally canceling the results of last year's parliamentary elections deemed fair by international observers.

Yushchenko in turn accuses pro-Moscow forces in parliament, led by Yanukovych's Regions party, of acting against the constitution by paying huge bribes to lure pro-Western deputies to their camp.

The European Union, Russia and the United States have all voiced concern, without explicitly taking sides.

The crisis comes after months of mounting tensions between Yanukovych, who favors strong ties with Russia, and Yushchenko, who came to power in 2005 promising closer relations with the West.

The two first faced off in 2004 presidential elections initially granted to Yanukovych, but then deemed fraudulent after mass protests known as the Orange Revolution.