Put into law, if a new Prime Minister is appointed, a General Election must be called within 90 days, so the new Prime Minister can obtain a mandate from the public, not just from their party.
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There is currently no requirement for there to be a General Election when a new Prime Minister is appointed. Both Theresa May and Boris Johnson called early elections after becoming Prime Minister, so as to get a mandate, but that’s no guarantee. As of writing Rishi Sunak has not called an election. This new law will ensure the public has a right to vote on who represents them, when a new Prime Minister is appointed.