Whitehall was cordoned off while police investigated an abandoned vehicle near Downing Street.
The street was closed in both directions between Trafalgar Square and Parliament Square.
The Metropolitan Police said in a statement on X, formally Twitter: “A cordon is in place at the southern end of Whitehall as a precautionary measure while officers investigate an abandoned vehicle in the vicinity of Downing Street.”
It is understood civil servants working inside government buildings on the road were unable to leave the building, and no one was allowed to enter.
It comes as a road traffic collision happened near Downing Street shortly before. The police said that the two incidents were not linked.
Transport for London (TfL) has advised commuters to avoid the Whitehall area due to closures and diversions affecting bus and vehicle traffic.
The Met Police later said the incident has been resolved and cordons will be lifted shortly.
