Isla Fisher Seen for the First Time After Sacha Baron Cohen Divorce News

Isla Fisher is telegraphing that her marriage to Sacha Baron Cohen is, in fact, over -- as if their divorce announcement wasn't enough ... she's now ditched her wedding ring.

The actress was photographed in North London this week, where she was walking her dog and chit-chatting on the phone ... and she was rolling by her lonesome here, rocking shades and holding a coffee, looking somewhat serious and downcast.

More importantly though is the fact that her left ring finger was bare ... namely, it was without her wedding band -- confirming she and Sacha are dunzo.

Remember ... the longtime couple announced last week that they were going their separate ways and divorcing, explaining they'd quietly filed for divorce .... which happened last year.

Unclear how long Isla's been going ring-less, but people are definitely taking notice now.

The notoriously private couple -- who share 3 children together -- asked for privacy as they navigated this new chapter for their family. There was no clear reason given for the split.

The divorce news came shortly on the heels of Rebel Wilson's new memoir, "Rebel Rising," in which she accused Sacha of acting inappropriately on "The Brothers Grimsby" set.

It definitely didn't paint Sacha in a good light -- despite his denial of her account -- and not long after ... it comes out that he and his wife are splitting up. Unclear if the book stuff had anything to do with them ending it ... on its face, it seems this was already happening.

Isla and Sacha's love story is coming to a close after over 20 years. Remember, they first met in 2001 and got engaged years later in 2004.

The duo finally wed in 2010 in an intimate ceremony in Paris.