The American President and the British Prime Minister are two of the most powerful leaders in the world.
The British Prime Minister is the head of state.
In the US, the President is the head of the government and the head of state.
People in the UK do not vote for the Prime Minister. Instead, they vote for a local member of Parliament.
In the US, there are two MPs who meet in London to discuss how they can make things better for everyone.
Then the party which has the most Prime Ministers is the one that gets to choose the Parliament
In the US, the Democrats decide who the President is
In the US, it is the party that picks the leader, in the UK, it is the people.
