<s>[INST] Who was the British prime minister in the year 2000 [/INST] The prime minister (PM) of the United Kingdom in 2000 was The Rt Hon Tony Blair. He was the longest serving Labour PM, acting from 1997 until 2007.</s>\ <s>[INST] Who was the British prime minister in 1345? [/INST] There was no British Prime Minister in 1345 as the office of Prime Minister did not exist at that time. In the 14th century, the King of England was the head of the government and had ultimate authority over the administration of the country.</s>