Police are to be given new powers to crack down on publicity stunts at government and royal properties.
The MI6 building is among the designated sites
Buckingham Palace, Chequers, Downing Street and GCHQ, in Cheltenham, will be among 16 "protected sites" from June.
The Serious Organised Crime and Police Act 2005 makes trespass on designated sites a specific offence subject to a prison term of up to six months.
Currently, trespassers cannot be prosecuted if they have committed no offence and agree to leave a location.
The offence was created after self-styled "comedy terrorist" Aaron Barschak gatecrashed Prince William's 21st birthday party at Windsor Castle in 2003 dressed as Osama bin Laden.
The designated sites will also include: Windsor Castle; St James's Palace; Highgrove House, Gloucestershire; the Palace of Westminster and Portcullis House; the Ministry of Defence main building in Whitehall and the London headquarters of MI5 and MI6.
"Existing powers do not provide a sufficient deterrent," a Home Office spokesman said.
"High-profile intruders not only waste valuable police time, but also endanger their own lives and the lives of others.
"Care has been taken to ensure that the boundaries of each site are permanent, continuous and clear to members of the public," he said.
Maps detailing the boundaries of the properties included are shortly to be published on the Home Office website.
The Attorney General will be required to give consent to any prosecution and people charged would be able to argue that they did not know a site was protected.