Sharing a picture of him and Nicola together, where she could be seen sporting an engagement ring, Brooklyn wrote: “Two weeks ago I asked my soulmate to marry me and she said yes xx
“I am the luckiest man in the world. I promise to be the best husband and the best daddy one day. I love you baby xx.”
Posting the same photo – which was taken by Brooklyn’s sister Harper – on her account, Nicola wrote: “You’ve made me the luckiest girl in the world. I can’t wait to spend the rest of my life by your side. your love is the most precious gift.
“I love you so so much baby and thank you harper for this pic,” the US actor added.
Brooklyn, 21, and Nicola, 25, have been dating for around eight months.
They went public with their relationship back in January, posting a black-and-white picture of themselves wearing towels.
Brooklyn and Nicola – who has starred in films such as Transformers and Back Roads, and is the the daughter of billionaire businessman Nelson Peltz and model Claudia Heffner – had spent lockdown in the US together.
They have since been reunited with Brooklyn’s famous family, who had been holed up at their home in the Cotswolds.