Kensit who was married to former Oasis singer Liam Gallagher, begins this role next month, where she will star as Emma Harding, "Lola Pearce's never-seen-before mother".
"It has always been a dream of mine to appear in EastEnders," she said. "The cast, producers, writers and crew have been wonderful, and I've had a ball. Thank you so much for having me".
The actress who is known for starring in shows Emmerdale and Holby City, will arrive on the Square "for a short stint".
EastEnders chief executive Chris Clenshaw spoke his delight that Kensit would be joining the soap's cast.
"We're delighted to welcome the wonderfully talented Patsy to the EastEnders family. She's the perfect fit to take on the role of such a long-awaited character that we know very little about", he said. "Softly spoken and measured, on one hand Emma is the very opposite of her long lost daughter, Lola. But on the other, there's a striking resemblance; successful, the capacity to hold her own – if she says she'll do something, she'll do it – and she's a fighter, just like Lola".
"Having spent a lifetime apart, Emma becomes desperate to make up for lost time, but her secret sadness and guilt are never far from the surface.
"The burden of losing her daughter has never left her, but can she find the courage to tell her shocking truth and reconnect with Lola, or will it come too little, too late?
"Patsy's portrayal is bound to set off fireworks in Walford and cause havoc for the Mitchell household".
Sharing details regarding Kensit's character, the BBC released this statement.
"Emma left Lola and her father behind when Lola was only three years old and has never been seen on screen before", they said. "But what has led to her explosive arrival on Albert Square, and how will Lola respond as she is forced to confront a face from her past when her own future is so uncertain?".
EastEnders airs on BBC from Monday to Thursday.
