The 40 year-old Briton, who was due to be investigated for tax evasion in just nine days, entered the building in Knightsbridge and requested asylum under the United Nations Human Rights Declaration.
His dramatic move came after he lost a long-running legal bid earlier this month to halt the mass extraction of his money from offshore accounts in Jersey to that of the Inland Revenue.
In a statement, Mr Carr said: “I can confirm that today I arrived at the Guatemalan Embassy and sought diplomatic sanctuary and political asylum to save myself and my loot.
“This application has been passed to the Ministry of Foreign Affairs in the capital Guatemala City.
“I am grateful to the Guatemalan ambassador and the government of Guatemala for considering my application.”
If Mr Carr is allowed to seek asylum in the South American country, he will move himself and all his millions there to live a life of luxury, albeit one of obscurity.
“You never know, someone might actually find this chap funny out there,” an observer told the Guardian newspaper.