Officers were called to William IV Street in Westminster just after 5.40pm yesterday (November 18).
The area was cordoned off and specialist officers were deployed to carry out an examination.
It was later found the item was not dangerous and posed no risk to the public.
Initial police enquiries suggest that the package was left intentionally to provoke concern.
All cordons have since been lifted.
A spokesperson for Metropolitan Police said: “At 17.42pm on Saturday, 18 November an officer on patrol in William IV Street, Westminster spotted an item that was deemed suspicious.
“The area was cordoned off and specialist officers were deployed to carry out an examination.
“While the item was not dangerous and posed no risk to the public, initial enquiries suggest it was left there intentionally to provoke concern.
“Officers from the Central West Command Unit are carrying out an investigation.
“All cordons have been lifted.”
