BBC Worldwide is partnering with Logo and BBC America for the series of specials.
"We are thrilled to be able to celebrate our 20th birthday with all of the original cast," Saunders said in a statement. "We hope that, like a good bottle of champagne, we have grown better with age but lost none of our sparkle."
Saunders, who wrote and created the series, plays Edina, a public relations professional who is always up on the current trends and fashions. Lumley plays Patsy, a hard-partying magazine exec.
The series debuted in 1992 before ending in 1996. It was revived for two new seasons in 2001 with a TV movie 'White Box' airing in 2004.
"Viewers in the US have been very kind to the show over the years and we are very happy to return on not one but two US channels at once, BBC America and Logo," Saunders said. "We fully intend to party like it's 1991. When we started filming in West London, it was like time had stood still. It was raining. Nevertheless we are so happy to be working for an audience that has grown just a tiny bit older, like us, but is still willing to let us fall over on TV in the name of PR."
Over the years, the series has aired in the US on Comedy Central, PBS, Oxygen, BBC America and Logo.
"People in the US have been fantastically loyal in their devotion to our show, so we really are thrilled to say that it's coming back for three new shows to celebrate our 20th anniversary," Jon Plowman, 'Ab Fab' executive producer, said in a statement.
"I can divulge that all of us have got a bit older, though we will be doing our best not to show it, and thankfully none of us have got any wiser. All of the originals who are back together again are still truly absolutely fabulous and we hope that the new adventures of Edina, Patsy, Saffy, Bubble and Mother, plus a few surprising guests, will entertain both our tried and trusted US fans as well as gain us some new friends. We are hugely grateful to BBC America and Logo for welcoming us all back with open arms."
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