The Duchess of Cambridge has hailed the “incredible achievement” of young British tennis star Emma Raducanu after she reached the US Open final.

Kate, a keen tennis fan and patron of the All England Lawn Tennis Club, sent the 18-year-old “the best of luck” ahead of her bid to win the grand slam tournament on Saturday.

Her messages, sent through the Duke and Duchess of Cambridges’ official Twitter account, comes after Raducanu became the first British woman to reach the final at Flushing Meadows since Virginia Wade won the title 53 years ago.

The royal tweet said: “What an incredible achievement at this year’s #USOpen @EmmaRaducanu!”

Including a fingers crossed emoji, it continued: “We will all be rooting for you tomorrow”, adding: “Wishing you the best of luck!”

The tweet was signed off “C”, the initial of the duchess’s full name, Catherine.

Prime Minister Boris Johnson also joined in the praise of the young tennis player on Twitter.

He tweeted: “Well done @EmmaRaducanu for a brilliant win at the #USOpen. The whole country will be cheering you on in the final.”