A few dozen men and youths tried to dismantle the wall of concrete blocks that blocked a street leading to Tahrir Square, focal point of demonstrations that broke out on January 25, 2010 and led to Mubarak's ouster 18 days later.
The walls were erected last year to protect numerous buildings housing government and security service offices in the area.
"Down with Mohamed Morsi," some demonstrators shouted. "Down with the power of the (Supreme) Guide" of the powerful Muslim Brotherhood, from whose ranks Morsi was elected last June.
Some demonstrators hurled rocks at riot police positioned a few dozen meters (yards) on the other side of the wall, who responded with tear gas grenades.
Opposition groups have called for mass street protests across the country on Friday against Morsi and the Brotherhood.
The National Salvation Front, the largest opposition bloc, has called for rallies "in all the Tahrir Squares of the country."
Authorities have vowed to keep security forces out of Tahrir Square to decrease the risk of confrontations, but said police would be in the surrounding areas to arrest troublemakers.