The couple is planning a "big engagement party" to celebrate their relationship milestone after Orlando Bloom popped the question to the 34-year-old singer last week.
A source told People magazine: "They are still busy enjoying and celebrating their engagement. They haven't shared any wedding details yet. They are planning a big engagement party for all of their friends.
"It will be very special. They are both so happy and excited to be engaged."
The news comes after it was recently revealed the Roar hitmaker was "shaking with happiness" when the Pirates of the Caribbean star proposed.
Orlando - who has an eight-year-old son called Flynn with his ex-wife, model Miranda Kerr - approached the proposal in a traditional way, seeking her parents' permission before he asked Katy to marry him.
The loved-up duo - who split in 2017, before rekindling their romance last year - are "over the moon" about the thought of married life.
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