It's a weekend of gridlock in parts of Toronto as the Gardiner Expressway closes until Monday morning for maintenance.

The downtown thoroughfare's westbound lanes are closed from Carlaw Avenue to the Humber River, and eastbound lanes from the Humber River to Spadina Avenue.

Both directions are expected to re-open by 5 a.m. Monday.

The city says crews are tackling a major job as they clean catch-basins and gutters, and repair the surface of the roadway.