Meryl Streep's daughter is engaged.

Actress Mamie Gummer has confirmed she is to marry actor Ben Walker after he proposed over the weekend.

She said: "He proposed a couple of days ago. He did it on one knee!"

Ben presented Mamie, 26, with a custom-made ring, and she admits the proposal came as a complete "surprise".

Mamie added her mother - who has four children with her sculptor husband Don Gummer - is delighted with the news.

She explained: "My mom loves him! We're all very happy."

Mamie and Ben have been dating for around 18 months.

They met while working on a film together, and went on to star alongside each other in Broadway play 'Les Liaisons Dangereuses' in spring 2008.

Meryl has previously admitted she was unsure whether she wanted her children to follow in her career footsteps as acting can be such a tough industry.

She said: "You just know what the road is. There's a lot of heartbreak, a lot of rejection, a lot of pain so it's hard to say, 'Sure honey, Take That job, because it's really tough.' "