Neeson, 56, left the set of "Chloe," a movie he was filming in Toronto, and rushed to his wife's side upon learning the news.
"'Chloe' will continue with its production schedule focusing on scenes which feature other cast members," the publicist for the film said in a statement to "Entertainment Tonight." "There are some scenes with Liam Neeson which have not been completed, however, we do not feel this is the time to address that matter. Our concern is for Liam and his family at this difficult time."
Richardson had two sons with Neeson, Michael, 13, and Daniel Jack, 12.
Following the news of Richardson's death, friends in Hollywood reflected on her career and legacy.
"Tash was the warm sun in the center of a large constellation of family, friends, all of those lucky enough to know her," Meryl Streep said in a statement to ABC News. "She is irreplaceable in our lives; she gave us so much, so generously -- her legacy is the love that connects us all."
Lindsay Lohan, who co-starred with the actress in 1998's "The Parent Trap," released the following statement through her publicist.
"She was a wonderful woman and actress and treated me like I was her own," Lohan's statement said. "I didn't see much of her over the years but I will miss her. My heart goes out to her family. This is a tragic loss."
Jane Fonda wrote about Richardson on her blog, saying that she met the actress on a movie set when Richardson was just a child.
"I first met her on the set of Julia [in which she starred with Vanessa Redgrave]. She was a little girl but already beautiful and graceful. It didn't surprise me that she became such a talented actor," Fonda said.
Ralph Fiennes appeared with the actress in the 2005 period drama "The White Countess."
"For everyone who knew and loved her, Natasha's death is a terrible, devastating loss. She was a star. A great actress, a beautiful woman, a fiercely loyal friend, a brilliant and generous companion. She was an adoring and loving wife and mother. She was unique. My thoughts and prayers go out to Liam and her beautiful sons, Micheál and Danny and to all her family," Fiennes told ABC News in a statement.
"I cannot imagine a world without her wit, her love, her mischief, her great, great talent and her gift for living. I loved her very much. She was a supreme friend. I shall miss her deeply."
"Natasha is irreplaceable," actress Mia Farrow said in a statement to reporters. "I cannot think of anyone kinder, more generous, thoughtful, smarter or more fun. She is the godmother of two of my children. The Neesons and Vanessa [Redgrave] have always made me feel a part of their wonderful family. My thoughts and prayers are with them."
"Natasha was brilliant, beautiful, funny, talented beyond measure, as emotionally raw as she was razor sharp," said Jodie Foster, who co-starred in 1994's "Nell" along with Richardson and Neeson. "May Liam, her beautiful boys and her loving family hold her close as they move through this tragic moment."
"She had an incredibly luminous quality, that you seldom see, and a great sense of humor," Dame Judy Dench said in a statement to reporters. "I thought she was a really great actress."