News of their romance came as a surprise after it was uncovered last month.
And Ewan McGregor, 46, who is estranged from wife Eve Mavrakis, looked smitten as he stepped out with his new girlfriend Mary Elizabeth Winstead, 32, in Hollywood, California on Saturday.
The Scottish actor looked undeniably trendy alongside his Fargo co-star as they coordinated in matching biker jackets while holding hands as they made their way down the street.
New couple: Ewan McGregor, 46, who is estranged from wife Eve Mavrakis, looked smitten as he stepped out with his new girlfriend Mary Elizabeth Winstead, 32, in Hollywood
Ewan looked happy to parade his new romance as he gripped the hand of Mary tightly while sauntering down the street.
The Star Wars star made an edgy statement in his black outerwear, which he paired with a simple white tee and light-wash denims.
His other half Mary seemed to source inspiration from his ensemble, as she too donned a super cool biker jacket which she kept zipped to show off her slender frame.
A pair of skinny jeans and knee-high black suede boots completed the look as she enjoyed the casual excursion with her other half.
Estranged: Ewan and Mary Elizabeth’s romance came as a shock to fans when pictures of the pair kissing on a dinner date emerged last month, before Ewan announced he had split from his wife Eve Mavrakis (pictured)
A couple that dresses alike…: The Scottish actor looked undeniably trendy alongside his Fargo co-star as they coordinated in matching biker jackets while holding hands
Fresh romance: Ewan looked happy to parade his new romance as he gripped the hand of Mary tightly while sauntering down the street
Super cool: The Star Wars star made an edgy statement in his black outerwear, which he paired with a simple white tee and light-wash denims
She wore her brunette shoulder length locks in a casual and relaxed manner and enhanced her striking features with a simple coat of make-up.
Strolling along in a pair of nineties grunge inspired lace-up boots, Ewan looked content – despite the recent controversy surrounding his new relationship.
He even proved to look undeniably happy and loved-up as he snuggled up to Mary, three weeks before the initial pictures emerged of then enjoying a cosy dinner date last month.
One diner exclusively told MailOnline that the pair had initially been sitting opposite each other for the meal, but the brunette beauty soon ran round to share a cuddle and a kiss with the Golden Globe nominee.
The diner remarked that the pair looked so cosy that he assumed the loved-up couple were Ewan and his French wife Eve, 51 – even remarking on how smitten they were ‘after so many years of marriage’.
Dressing alike: His other half Mary seemed to source inspiration from his ensemble, as she too donned a super cool biker jacket which she kept zipped to show off her slender frame
Trendy: A pair of skinny jeans and knee-high black suede boots completed the look as she enjoyed the casual excursion with her other half
Stunning: She wore her brunette shoulder length locks in a casual and relaxed manner and enhanced her striking features with a simple coat of make-up
The onlooker said: ‘I saw him sitting there and didn’t think anything of it. I recognised him and I thought I’d take a picture to show my family. I didn’t think anything of it at all until I saw the story about how he had left his wife.
‘When I saw them in the restaurant I actually thought it was him and his wife.
The diner added: ‘I commented to the person I was with that after being married so long it was nice they were so lovey dovey. He said to me “maybe it’s not his wife” Turns out it wasn’t.
She was initially sitting opposite him. She got up and he was messing about on his phone… She came back and sat with him, arms around his neck.
‘There was lots of kissing and cuddling going on.’
Happy: Strolling along in a pair of nineties grunge inspired lace-up boots, Ewan looked content – despite the recent controversy surrounding his new relationship
‘There was lots of kissing and cuddling’: An onlooker described their cosy date together last month – which occurred before Ewan had revealed he was estranged from wife Eve
Ewan and Mary Elizabeth’s romance came as a shock to fans when pictures of the pair kissing on a dinner date emerged last month, as Ewan had not announced his split from his wife.
The new couple starred together in the FX series Fargo – where Mary Elizabeth played his sexy love interest Nikki Swango.
Meanwhile, Ewan and his estranged wife Eve met on the set of TV show Kavanagh QC before Ewan became a big name in Hollywood. They share four children together.
Ewan’s wife of 22 years, Eve, has been staying in America with their four daughters since the first pictures of the actor and his new lover emerged.
According to reports last week, Eve feels ‘sick and furious’ at the affair allegations. The French production designer, who has been seen without her wedding ring, is trying to remain as ‘dignified’ as possible.
Different countries: Ewan’s wife of 22 years, Eve, has been staying in America with their four daughters since the first pictures of the actor and his new lover emerged
She did not know the actress had had a ‘teenage crush’ on her husband when she had her over for dinner with their children in Los Angeles last December while the two were filming Fargo.
A source told The Sun: ‘She is doing her best to handle it with dignity. But what makes it worse is she has been told Mary Elizabeth had a teenage crush on Ewan. I’m sure a lot of people did but they didn’t go and have an affair with him.’
They added: ‘Mary went to the house once and met Eve and the kids over dinner. She was very cordial. It seemed logical she should get to know Ewan and the family.’
Fargo began shooting in January and Eve visited her husband on the set in Canadian city Calgary.
Ewan and Mary, who filmed a racy nude love scene in a bath for their on-screen romance in the most recent series of Fargo, were seen getting close during a meeting at The Good Life Eatery in London’s St. John’s Wood on October 7.
It has since emerged that Ewan and his wife had split months earlier – in May – the same month Mary Elizabeth announced her separation from her husband Riley Stearns.
No longer together: Ewan and his wife split in May the same month Mary Elizabeth announced her separation from her husband Riley Stearns