The star of Prime Suspect and The Queen famously took part in an awkward interview with the late chat show host in 1975 in which he asked her if her "equipment" hindered her performance.
Mirren has now told the Radio Times: "I didn't feel sorry for Parky, but then in a way I did because in lots of ways he was right.
"My physicality did get in the way of me being taken seriously as a classical actress."
She added: "Also, I was listening to Elton John's autobiography and I didn't realise that when Elton John was outed in a bad way by The Sun, Parky invited Elton on to his show so that they could talk about it properly.
"He held out a hand and helped Elton John at a very important moment. So I don't want to diss Parky."
When the Golda star appeared on Parkinson's chat show in 1975 he introduced her the "sex queen" of the Royal Shakespeare Company and quoted critic's description of her as projecting "sl*ttish eroticism".
Parkinson – who died at the age of 88 in August – then went on to ask Mirren: "Do you find, in fact, that this, what could be best described as your equipment, in fact hinders you perhaps in that pursuit? Well, your physical attributes... your figure?"
Mirren replied: "Serious actresses can't have big bosoms, is that what you mean?"
He replied: "I think that they might detract from the performance, if you know what I mean."
Afterwards Mirren called Parkinson a "sexist old fart" and said the interview has been "enraging".
Parkinson always refused to apologise. In 2016, he told the Mail: "Maybe I was a bit over-reactive to Ms Mirren. On the other hand, she presented a provocative figure as she walked down the stairs carrying a feather boa, half dressed as I recall, with love and hate tattooed on her knuckles. I mean, we didn’t like each other.”
He added: "“There is no need to apologise, not at all. I’ve not done anything that I’m ashamed of. Am I sexist? No, I’m Yorkshire.”
Piers Morgan asked him on ITV's Life Stories in 2019 if in hindsight he thought the comments were sexist.
Parkinson replied: "Well, maybe. But nobody got hurt, nobody died."
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