10 Downing Street

n. address of the home and office of the British prime minister

10 Downing Street is the residence and office of the Prime Minister of the United Kingdom and the headquarters of Her Majesty's Government. It is situated on Downing Street in the City of Westminster in  London, England. It is actually the official residence of the First Lord of the Treasury, but in modern times this post has always been held simultaneously with the office of Prime Minister.
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