Guernsey's Lieutenant Governor will ratify laws from the end of this week.
It replaces the process of primary legislation going before the UK Privy Council for Royal Assent.
Eight years ago, a review for Guernsey's States recommended changing the process.
It was agreed last May by Guernsey, Alderney and Sark's parliaments that responsibility should be delegated to the Lieutenant Governor.
Now, His Majesty the King has approved the change, and it will take effect on Thursday 29 February.
The aim is to speed up the time it takes to enact local laws, as it will no longer rely on when the sovereign's advisers meet.
Some Projets de Loi will still be specifically reserved for His Majesty's Assent, such as those involving defence matters.
The government says the change to the Royal Assent process ' underlines the Bailiwick’s domestic legislative autonomy and developing international identity'.
Policy and Resources Committee President Deputy Lyndon Trott has welcomed the change:
"Following years of work, and noting the benefits of an expedited process, I am pleased this change has now been agreed. This new process is not only of practical importance, it also reflects our identity as a jurisdiction through our direct relationship with the Crown, distinct from the UK.”

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