The 53-year-old Wolverine actor was married to Deborra-Lee Furness, 67, for 27 years and was pictured over the weekend without his wedding ring.
On Monday, the A-lister was joined on a walk by his fellow actor friend and appeared sombre as they wandered around the streets of New York City.
Hugh was seen wearing a black jacket that featured a plethora of pockets which he zipped up halfway and a white t-shirt underneath.
He finished off his simple, casual outfit with some baggy black trousers and black and white trainers.
The star sported a salt and pepper coloured bushy beard and remained stony-faced as he sauntered alongside his friend.
Ryan, 46, followed suit and adopted a similarly casual looking ensemble that consisted of a black wind-breaker rain jacket and some grey trousers.
He wore a navy crest emblazoned cap on his head and some polka dot socks inside a pair of white trainers.
News of their separation was shared in a statement published by People magazine on Friday that read: ‘We have been blessed to share almost three decades together as husband and wife in a wonderful, loving marriage.
‘Our journey now is shifting and we have decided to separate to pursue our individual growth.
‘Our family has been and always will be our highest priority. We undertake this next chapter with gratitude, love and kindness.
‘We greatly appreciate your understanding in respecting our privacy as our family navigates this transition in all of our lives.”
The statement, signed ‘Deb and Hugh Jackman’, ended: ‘This is the sole statement either of us will make.’
Hugh and Deborra had met on the set of Australian TV show Correlli in 1995 and the pair were married for almost three decades, having wed on April 11 1996.
In April, the star – known for his roles in The Greatest Showman, Les Miserables and the X-Men films – posted a tribute to his wife on Instagram on the day of their anniversary.
It said: ‘I love you Deb. Today is our 27th wedding anniversary. 27 YEARS!!
‘I love you so much. Together we have created a beautiful family. And life.
‘Your laughter, your spirit, generosity, humor, cheekiness, courage and loyalty is an incredible gift to me. I love you with all my heart.’
The pair had two adopted children together called Oscar and Ava.