Michelle Williams poses with Mila Kunis at Oz photocall as it emerges she has 'split from Jason Segel'

PUBLISHED: 04:22 EST, 27 February 2013 | UPDATED: 06:28 EST, 27 February 2013

It was revealed on Tuesday that she has split from Jason Segel after a year of dating.

But Michelle Williams did her best to put her personal dramas behind her on Wednesday, as she joined her Oz: The Great And Powerful co-stars Mila Kunis and James Franco at a photocall for the movie in Moscow, Russia.

The 32-year-old actress smiled through any pain she was feeling and appeared in relatively good spirits for the event, looking as stunning as ever in a black tiered minidress.

Smiling through the pain: Michelle Williams appeared in good spirits at a photocall for Oz: The Great And Powerful on Wednesday in Moscow, Russia, following reports she has split from Jason Segel

Mother-of-one Michelle, who plays the good witch Glinda in the Disney movie, teamed the ensemble with a black shirt under the outfit, and finished it off with a quirky pair of star-print heels.

Meanwhile, Mila, who plays Theodora in the film, opted for a figure-hugging grey dress with frill detailing down the front.

The 29-year-old injected some fun into her outfit with a pair of leopard-print Christian Louboutin heels.

Style competition: Michelle looked cute in a black tiered dress while her co-star Mila Kunis went for a figure-hugging grey dress with frill detailing and some leopard-print heels

All-star cast: The duo were joined by co-star James Franco as well as director Sam Raimi for the event

The actresses were joined by co-star Franco and director Sam Raimi as they posed on the balcony of a hotel in the Russian city.

It was revealed on Tuesday that Michelle and Jason, 32, had 'quietly ended their romance earlier this month' after struggling with the long-distance aspect of their relationship, according to Us Weekly magazine.

Jason lives in Los Angeles, California, where his CBS sitcom is filmed and Michelle lives with her seven-year-old daughter Matilda in New York.

Beaming: Michelle looked radiant for the event, and kept her make-up simple

Meet and greet: The cast later spoke to the press during a conference to promote the film

The pair were only recently photographed together looking happy as they celebrated the New Year with Michelle's best friend Busy Philipps and her husband in Mexico in January.

The couple had been dating since the start of 2012 and were believed to be introduced by Busy.

Since then Jason has developed a strong relationship with Michelle's daughter Matilda, whom she had with the late Heath Ledger.

It is over: Michelle and Jason, seen here in Los Feliz, California, in August, are said to have split due to struggling with the long-distance aspect of their relationship

Jason was the first man that actress was publicly seen dating since Heath died of a drugs overdose in 2008 - five months after they had separated.

The couple were often seen walking around New York with Jason taking on father duties with the little girl.

Jason and Michelle initially avoided confirming their relationship even though The Five Year Engagement star had been was spotted playing with Matilda and was photographed with a picture of Michelle with the phrase 'I Heart U' showed up taped to the back of his iPhone.