At 43 , he is the youngest prime minister since Robert Banks Jenkinson , the 2nd Earl of Liverpool in 1812 . He is six months younger than Tony Blair when he entered Downing Street in 1997 . Like Mr Blair , he has a young family and an informal , self-consciously modern approach to politics . Mr Blair arrived at Number 10 with a guitar case in hand . Mr Cameron has his cycling helmet on his handlebars and fondness for indie rock . Yet despite opening himself up to the TV cameras like few other British political leaders , Mr Cameron is still something of an unknown quantity .
British Prime Minister David Cameron , left , meets Wimbledon winner Andy Murray in front of No 10