Naomi Watts and Reese Witherspoon sent heartfelt birthday messages to Nicole Kidman on Wednesday (20.06.17).

The 'Lion' actress turned 50 this week and her close friends used social media to send their best wishes for the day.

Naomi shared a picture of herself and her old friend and wrote: ''Happy Birthday to this beautiful woman. A remarkable human who gives so much love and spirit to all those around her.

''My friend, I am so happy to have shared incredible experiences with you over the last 3 decades. May there be many more to come.(sic)''

And Reese also used Instagram to send a message to her ''dear friend'' and 'Big Little Lies' co-star.

Alongside a picture of her and her pal, she posted: ''Wishing a big happy birthday to my dear friend, the one and only, mega-talented, #NicoleKidman!! I hope you have a gorgeous day filled with laughter and love.

Love you, lady!! (sic)''

Nicole - who has kids Isabella, 24, and Connor, 22, with ex-husband Tom Cruise, and Sunday, nine, and Faith, six, with spouse Keith Urban - recently admitted she wasn't planning a particularly wild celebration for her milestone birthday.

She said: ''[I want] to hang with my divine husband and my kids and my sister ... I've already been to Australia and saw my mom and it's too far for her to travel but my sister is coming over with all her children. She has six kids.

''That's it for me. I don't need any big parties; I just need my family around me. If I have my family around me I am happy.''

And the 'Paddington' star recently insisted she is ''embracing'' turning 50.

She said: ''I'm absolutely embracing it. I try to embrace all parts of my life now because I think you just go 'wow. I'm so lucky, so blessed.''