The EastEnders star will play Phoenix in an upcoming BBC Four drama about the origins of the ITV soap. She told PA that the actress, famed for playing Elsie Tanner, reminded her of her grandmother.
"I've always loved Pat Phoenix," she said. "She reminds me of my nan. I used to tell my nan she looked like Elsie Tanner and here I am playing her."
She continued: "My nan was very glamorous, but she was a tough lady as well. I used to sit there watching Corrie with her and she always had lipstick on."
Wallace, who will soon return to Albert Square as Kat Moon, compared the "glamorous and gorgeous" Phoenix to Sofia Loren.
"She was a real woman, I think. She didn't mince her words," she added.
Celebrating the soap's 50th anniversary, The Road To Coronation Street will air on BBC Four at 9pm on September 16.
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