<P> Downing Street is a street in London, United Kingdom, known for housing the official residences and offices of the Prime Minister and the Chancellor of the Exchequer . "Downing Street" is used as a metonym for the Government of the United Kingdom . </P> <P> Downing Street is off Whitehall in central London, a few minutes' walk from the Houses of Parliament and a little further from Buckingham Palace . The street was built in the 1680s by Sir George Downing . The houses on the south side of the street were demolished in the 19th century to make way for government offices now occupied by the Foreign and Commonwealth Office . </P> <P> For more than three hundred years it has held the official residences of the First Lord of the Treasury, an office now synonymous with that of Prime Minister, and the Second Lord of the Treasury, an office held by the Chancellor of the Exchequer . The Prime Minister's official residence is 10 Downing Street; the Chancellor's official residence is next door at Number 11 . The government's Chief Whip has an official residence at Number 12, although the current Chief Whip's residence is at Number 9 . </P> <P> The street was built in the 1680s by Sir George Downing, 1st Baronet, on the site of a mansion, Hampden House . What was on the site before the mansion is vague, but there is evidence towards a brewhouse called The Axe, owned by the Abbey of Abingdon . Downing was a soldier and diplomat who served under Oliver Cromwell and King Charles II, and who invested in properties and acquired considerable wealth . In 1654, he purchased the lease on land east of Saint James's Park, adjacent to the House at the Back, and within walking distance of parliament . Downing planned to build a row of townhouses "for persons of good quality to inhabit". However, the Hampden family had a lease which prevented their construction for 30 years . When the Hampden lease expired, Downing received permission to build further west to take advantage of recent developments . The new warrant issued in 1682 reads: "Sir George Downing...(is authorised) to build new and more houses further westward on the grounds granted him by the patent of 1663 / 4 Feb. 23 . The present grant is by reason that the said Cockpit or the greater part thereof is since demolished; but it is to be subject to the proviso that it be not built any nearer than 14 feet of the wall of the said Park at the West end thereof ." </P>

Who lives next door to the prime minister