We look at the many responsibilities the prime minister has - and what they do on a daily basis 👇
But despite having held the second most senior job in government, Mr Sunak still has a lot to prove.
The PM is also responsible for resolving disputes between different government departments - on policy and how much funding they get - and various members of the cabinet. Prime ministers can decide how involved they want the cabinet to be in decision-making and how many cabinet committees they chair themselves.
This saw her intervene with her and Kwasi Kwarteng's energy price guarantee and"mini-budget", which included numerous tax cuts and U-turns of Boris Johnson's policies. Tuesday evenings and Wednesday mornings are dominated by preparing for Prime Minister's Questions at midday on Wednesday.Rishi Sunak on a visit with Network Rail staff