The Prime Minister's Office has been placed under lockdown as police moved Downing Street staff into "secure rooms".

A police cordon has been erected on Parliament Street this afternoon while officers investigate an "abandoned vehicle".

Four police vans are also blocking the route to the official residence of Sir Keir Starmer.

Downing Street is closed in both directions between Trafalgar Square and Parliament Square.

It it believed that civil servants working inside government buildings in the area are unable to leave, and nobody is allowed to enter.

A spokesperson for City of Westminster Police said: "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 not linked to a separate road traffic collision involving a coach and a pedestrian in nearby Abingdon Street."