As well as being head of government, a prime minister may have other roles or titles—the Prime Minister of the United Kingdom, for example, is also First Lord of the Treasury and Minister for the Civil Service. Prime ministers may take other ministerial posts—for example, during the Second World War, Winston Churchill was also Minister of Defence (although there was then no Ministry of Defence), and in the current cabinet of Israel, Benjamin Netanyahu also serves as Minister of Communications, Foreign Affairs, Regional Cooperation, Economy and Interior

What are two other job titles of the Prime Minister of the  UK?