Venezuela's government-stacked Supreme Court is blocking one of the nation's most prominent opposition leaders from leaving the country and requesting that his immunity from prosecution be lifted.

The court said Friday that Freddy Guevara is suspected of instigating unrest and other crimes presumably committed during four months of anti-government protests this year.

Guevara was at the forefront of opposition protests that mobilized thousands of Venezuelans frustrated with their nation's spiral into political and economic calamity.

His Popular Will party called the accusations "inexistent crimes invented by the dictatorship."

By law, the opposition-controlled National Assembly is charged with determining whether a legislator's constitutional immunity should be stripped. But the court has instead referred the case to a pro-government assembly ruling with virtually unlimited powers.