Initial results of diagnostic tests by the Klokner Institute highlighted damaged to a section of Liben Bridge over the Vltava River. The bridge's dangerous state has resulted in it being graded at the worst level on a seven-point scale.
The city authorities were advised that vehicles up to 5t could continue to use the bridge, but decided to take the safer option of banning all cars, buses, lorries and trams for the time being.
Emergency repairs are expected to take at least three weeks.
The complete report with the results of all diagnostic measurements is due by the end of the month. It will include a detailed report and recommendations for repairs.
The concrete bridge, which is about 90 years old, has five arch spans of between 28m and 43m and an overall length of 780m including approaches.