Pippa Middleton and hedge fund manager James Matthews have confirmed they are engaged to be married.
In a statement, Miss Middleton - the younger sister of the Duchess of Cambridge - and Mr Matthews said they are planning to marry next year.
The couple became engaged on Sunday - reportedly during a trip to the Lake District.
The Duke and Duchess of Cambridge are "absolutely delighted", a Kensington Palace spokesman said.
Miss Middleton was the maid of honour when the duchess married Prince William in 2011.
Her father, Michael Middleton, said he and his wife Carole were "absolutely thrilled" with the news.
"They make a wonderful couple and we wish them every happiness together," he added.
Miss Middleton was wearing her engagement ring as she was pictured leaving her house this morning.
The couple are reported to have been dating for about a year and were photographed at Wimbledon.