Kaley Cuoco is engaged to equestrian Karl Cook.

The 32-year-old actress and her beau have decided to take their romance to the next level, as Karl has proposed to Kaley on her 32nd birthday after two years of dating, and he has shared the special moment he popped the question on social media.

In the footage, which has been posted on Karl's Instagram account, 'The Big Bang Theory' star can be seen getting emotional after the surprise proposal she had to fight back the tears to say, ''Yes''.

In the video Kaley can be seen sobbing before she holds up a diamond ring on her finger to camera.

He captioned the post: ''Well after nearly two years I finally got up the courage to ask her to marry me. This is the best night of my life and I think the video shows it is the best night for kaley as well.....of she said yes!!!!! (sic).''

The clip shows an emotional Kaley flashing her sparkler and blurting out, ''We're engaged!''

When Karl says, ''You still haven't said yes yet,'' she shouts, ''Yes! I say, 'Yes!' I say, 'Yes!'''

Karl has since shared a close-up image of the engagement ring on the photo-sharing site, and has admitted he is ''so so so happy'' the pair are engaged.

The post read: ''I am so so so happy. Thank you @nadis_diamonds for making the greatest ring I could hope for. Absolutely brilliant. Thank you thank you (sic).''

Kaley - who was previously married to tennis player Ryan Sweeting in December 2013 but divorced two years later in 2015 - is thoroughly smitten with her partner.

Speaking previously, Kaley said: ''I feel very, very lucky that I found someone like him. I've never felt happier.He's a real person and I think the big deal was knowing how much he loves dogs and horses - that's always on my checklist. 'Must love dogs' is number one and he checked that off quite quickly and I fell very hard.''