Published Monday, 16 May 2011
The threat, said to be "non-specific", was passed on to authorities in the city on Sunday night.
Parts of London were cordoned off on Monday morning amid a heightened police presence.
"A bomb threat warning has been received relating to central London today," Scotland Yard said.
"The threat is not specific in relation to location or time."
Republican dissidents have been linked to the warning, which comes before the start of the Queen's historic four-day trip to the Republic Ireland, the first ever by a British monarch.
"Policing operations and contingency planning remain under constant review and a wide range of overt and covert tactics will continue to be used in London," a statement from the Metropolitan Police said.
"At this time Londoners should continue to go about their business as usual but we encourage the public to remain vigilant and report any information about unusual activity or behaviour which may be terrorist-related."