Colin Firth's estranged wife hailed the actor as her ''best partner in crime ever'' on Thursday (10.09.20).

The 'Bridget Jones' Diary' star split from Livia Giuggioli in December after 22 years of marriage, but the 51-year-old producer marked the actor's 60th birthday with an affectionate Instagram post.

Sharing a photo of Colin wearing Sir Elton John's costume from their 2017 movie 'Kingsman: The Golden Circle', Livia wrote on Instagram: ''60th and not feeling it [heart eye emoji].

''happy birthday to the best partner in crime ever (for the last 25 years and counting) [butterfly and rainbow emojis] (this when Colin stole Elton John costume on the Kingsmen set ... [cry laughing emoji]) #thursday #thursdayvibes.(sic)''

Just weeks after announcing their separation, the former couple - who have sons Luca, 19, and Matteo, 17, together - got together to ring in the new year.

At the time, Livia shared a slideshow of pictures featuring Colin and some friends and wrote: ''How we ended and how we began [heart emoji] @massimoserini.official @karenalder @sarahdeweymassage Colin and many more [heart emoji] bye 2019 and helooooooo new decade! ??? (sic)''.

And Colin and Livia hosted a screening of Netflix's 'The Great Hack' in January, even posing for a photo together.

Back in 2015 and 2016, Colin and Livia split for a short period of time where she briefly dated Marco Brancaccia, who she later accused of stalking her.

In a statement, they said at the time: ''A few years ago Colin and Livia privately made the decision to separate. During that time Livia briefly became involved with former friend Mr. Brancaccia. The Firths have since reunited.

''Subsequently, Mr. Brancaccia carried out a frightening campaign of harassment over several months, much of which is documented. For obvious reasons, the Firths have never had any desire to make this matter public.''

Brancaccia denied the allegations, insisting they were ''romantically involved'' and the pair's marriage had been ''over for years''.

He said: ''She wanted to leave Colin for me. The marriage had been over for years. My 'stalking' consisted of two messages via WhatsApp after she ended our relationship in June 2016, and an email.

''I wrote an email to Colin about my relationship with Livia, which I now regret sending, and she filed a complaint against me for stalking out of fear that I could go public with what she had revealed to me about her marriage and work.''