PRAGUE, Czech Republic — Former Czech President Vaclav Havel had harsh words for Russia’s current regime during 20th anniversary celebrations of the Velvet Revolution.

“The era of dictatorships and totalitarian systems has not ended at all. It may have ended in a traditional form as we know it from the 20th century, but new, far more sophisticated ways of controlling society are being born,” Havel told students Saturday in a political debate at Charles University’s Faculty of Arts.

He said Russia had developed a special, sophisticated way of general manipulation, and while displaying the attributes of democracy, its practice was limited to a level that would not harm the current regime.

Later Saturday, at a concert featuring underground rocker Lou Reed, soprano Renee Fleming and folk singer Joan Baez in a 13th-century church in downtown Prague, Havel called for international solidarity with the oppressed people around the world from North Korea to Venezuela.

Baez performed “We Shall Overcome” in both Czech and English to massive applause by an audience that included former U.S. Secretary of State Madeleine Albright, who was born in Prague.

Video messages from former Soviet leader Mikhail Gorbachev, U.S. President Barack Obama and German Chancellor Angela Merkel were broadcast along with greetings from rockers Mick Jagger and Bono during the nationally televised concert. Gorbachev praised the peaceful nature of the Velvet Revolution, while Obama said, “Your spirit, your courage, inspired the world.”

Havel, now 73, was co-author of the Charter 77 human rights manifesto and spent several years in Communist prisons before becoming Czechoslovakia’s first president after the peaceful 1989 revolution toppled the regime.