image source, Getty Imagesimage captionWillie Garson was best-known as Stanford Blatch in Sex and the City

Willie Garson, the actor best known for playing talent agent Stanford Blatch in Sex and the City, has died at the age of 57, his son says.

In the hit HBO series, he played the role of close friend and confidante of Sarah Jessica Parker's Carrie Bradshaw. Most recently, he had been working on the spin-off series And Just Like That.

Garson was also known as conman Mozzie in the TV series White Collar.

The cause of his death has not been disclosed.

Born William Garson Paszamant in New Jersey in 1964, Garson studied theatre and received a masters of fine arts from Yale School of Drama.

He then took on small roles in several popular television series in the 1980s, including Cheers, Family Ties and LA Law. He also appeared in some hit programmes of the 1990s such as The X-Files, Boy Meets World and Friends.

In 1998, Sex and the City debuted and Garson appeared throughout the seasons as Stanford Blatch, a role he reprised in the franchise's two films.

Mario Cantone, who played Garson's on-screen partner Anthony Marentino in the series, wrote on Instagram: "I'm devastated and just overwhelmed with sadness… You were a gift from the gods."

Cynthia Nixon, who played Miranda Hobbes in the series, said: "We all loved him and adored working with him. He was endlessly funny on-screen and in real life. He was a source of light, friendship and show business lore."

image source, Getty Imagesimage captionSarah Jessica Parker and Willie Garson on the set of Sex and the City in 2007

The executive producer of Sex And The City and Just Like That, Michael Patrick King, said Garson had been working "even while he was sick", without giving details.

"His spirit and his dedication to his craft was present every day," he said in a statement. "His multitude of gifts as an actor and person will be missed by everyone."

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His film credits include Groundhog Day, There's Something About Mary, and Fever Pitch.

Garson was also a strong advocate for adoption and, in 2009, adopted his son Nathen, who shared a tribute on Instagram.

"I'm so glad you got to share all your adventures with me and were able to accomplish so much," he said. "I'm so proud of you. I will always love you, but I think it's time for you to go on an adventure of your own."

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