Heidi Klum announces her engagement to boyfriend Tom Kaulitz

Supermodel Heidi Klum, 45, is set to marry 29-year-old musician Tom Kaulitz.

The former Victoria’s Secret model, shared the news with her 5.6million Instagram followers on Christmas Eve, posting an ecstatic close-up black and white picture of the very happy couple.

In the photograph Heidi’s huge three-stone engagement ring is clearly on show, and the image is simply captioned with the words: ‘I SAID YES!’ and a heart emoji.

https://www.instagram.com/p/Brx_MhbDhTT

Since sharing the news, the post has gained thousands of comments and more than 679K Likes from overjoyed fans, including Mel B, Rita Orla and Gwen Stefani.

The American’s Got Talent judge and her partner, who is a guitarist in the band Tokio Hotel, went public with their relationship back in May after they were spotted kissing on the set of the popular talent show.

Gushing about her now fiancé, Heidi recently told People magazine: 'He is the kindest, sweetest, most caring, loving person. I feel so lucky. I don’t know the last time I was this happy in my life.'

Their engagement comes four years after the German model became officially divorced from musician Seal in 2014, though the pair separated in 2012.

Model Heidi Klum was previously married to Kiss From a Rose singer, Seal

The pair, who were together for over 10 years  and famously renewed their wedding vows several times, share four children together – Henry, 13, Johan, 12, Lou, nine, and daughter Leni, 14.

Heidi Klum hits back at mum-shamers who criticise her daughters

Heidi was pregnant with Leni, whose biological father is Flavio Briatore, when the couple first got together – and Seal went on to adopt her.

This will be Tom's first marriage, but the third for The Project Runway host. Heidi also tied the knot with Australian stylist Ric Pipino, who she was married to from 1997 to 2002.

Huge congratulations to the happy couple!