ST PETERSBURG: Over 2,000 people rallied in St Petersburg on Saturday to protest plans by the city authorities to give a landmark cathedral to the Russian Orthodox Church amid an increasingly passionate debate over the relationship between the church and state.

"We won't give St Isaac's to the church. We want to save it as a museum," Boris Vishnevsky, a local lawmaker, told protesters in central St Petersburg.

"St Isaac's Cathedral is part of our cultural heritage. There are so many valuable exhibits that require the work of museum specialists. The Russian Orthodox Church does not have those specialists," said Irina Azbel, 43, a doctor, who was among those protesting.

The rally was significantly larger than a similar demonstration attended by several hundred people earlier this month.

A few dozen counter-protesters gathered in the same place to support the plans. "The return of the cathedral to the church is a return to our national roots," said Yelena Semyonova, 52, a professor.

The announcement earlier this month that the neoclassical St Isaac's Cathedral, which is currently run as a museum, will be put under Orthodox Church ownership has sparked a backlash from city residents. More than 200,000 people have signed an online petition calling on the city authorities to reconsider.

Prominent cultural figures including the director of St Petersburg's world-renowned Hermitage Museum have criticised the decision.

Speakers at Saturday's protest said that the gathering was the first stage of a civil campaign aiming to keep St Isaac's under state control.

St Isaac's, one of the most visited tourist sites in Russia's old imperial capital, has been a museum since 1917. Some experts are concerned that when it gains ownership the Orthodox Church will neglect the exhibits on display, which include a rare Foucault pendulum.

The handover has been seen as indicative of the growing power of the Orthodox Church and part of a trend of social conservatism in Russia, where President Vladimir Putin has appealed to traditional values as opposed to Western liberalism to help tighten his grip on society.