Mikov said Tuesday night's blockade of Parliament was deliberately staged by "irresponsible politicians," Novonite.com reported.
"Looking for democratic and legal solutions within the framework of the Constitution is getting harder and harder," Mikov said. "That is why I called on MPs to not go to work Wednesday. MPs have been elected not in order to work under [an ultimatum], pressure and danger for their lives."
For weeks, GERB has boycotted the work of Parliament. On Tuesday, when party members returned to the Capitol to discuss a proposed budget, thousands of protesters blockaded the building, forcing members of Parliament to be held inside for several hours until police could safely escort them out, Novonite.com said.
Trapped inside were 109 lawmakers, staffers and journalists.
Opposition and one-time ruling party GERB responded by calling for Mikov's resignation, saying he doesn't have the power to cancel a scheduled parliamentary session.
"Yesterday's situation again shows that irresponsible politicians are putting a stain on Bulgaria," Mikov said during a joint news conference with ruling Bulgarian Socialist Party leader Sergey Stanishev Tuesday. "We expect that the police, prosecution, and Sofia municipality will start strictly applying the laws of the country."
Also Wednesday, GERB urged Prime Minister Plamen Oresharski to resign and called for early elections.
Protesters have been demonstrating throughout Bulgaria for 41 days, demanding that Oresharski resign following several controversial appointments.