Heidi Klum and musician Tom Kaulitz become engaged.

Heidi Klum, a supermodel, TV personality, and businesswoman, revealed

her engagement to musician boyfriend

Tom Kaulitz on Monday in an Instagram post.

The 45-year-old German model posted a heart emoji along with the comment,

"I SAID YES," in response to the image.

the couple was shown in a black-and-white picture

 Klum flashing her diamond ring

 In May, the two disclosed their relationship to the public.