RIA Jones is arguably the closest thing you’re going to get to musical theatre royalty. At 19 she became the youngest person ever to play the lead in Evita and followed that by making her West End debut in Chess.

Think of the most popular musicals of recent times and the chances are that Ria has starred in them.

It is therefore surprising when she describes her role as Mama Rose in Gypsy which is running throughout the festive season at Manchester’s Royal Exchange Theatre as ‘the biggest role of my career’.

“I really believe that, particularly the more I have got into the role,” she said. “Playing Norma Desmond in Sunset Boulevard was big; Evita was clearly big but this is a different level.

“It’s the most text I’ve ever had to deal with and the journey she takes from the beginning to the end is just huge.”

Gypsy is the story of Rose and her two daughters June and Louise. Rose is determined that June is going to be a vaudeville star and works tirelessly to achieve this. When June decides she can’t cope with the pressure, Rose turns her attentions on making Louise a star instead.

Based on the memoirs of Louise - who as Gypsy Rose Lee was the highest paid burlesque star in the world - Rose is a hugely complex character.

“She’s extremely driven,” said Ria, “but you have to understand her own background where she was abandoned by her mum and left with her father with whom she had a very difficult relationship.”

Stories of pushy mums in showbusiness abound, but Ria is determined that Rose should not just be seen in such a one-dimensional way.

“I’ve had lots of experience of stage mums,” she said. “I’m lucky that my mum was an opera singer and my father was a singer as well so I was brought up in a theatre household. Music and the theatre was always in my home growing up and from the age of three I went to dance classes and I always performed.

“But seeing how other mums were compared to my own mum, I realise I was lucky. She was never pushy, she never pushed me and yet she always supported me.”

Although Ria admits her mum was nothing like Rose, she has brought a little of her mum into her performance.

“Oh, there are bits of my mum in there,” she laughed. “My mum brought me up beautifully but I do remember appearing on stage for the first time and my mum was accompanying me on the piano and she’d be mouthing the words to me as she played because I was scared I’d forget them – she’s stopped doing that now by the way, that would just be embarrassing!”

With lyrics by Stephen Sondheim, Gypsy features well known songs such as Everything’s Coming Up Roses and Together but having prepared for the role, Ria no longer classes the show as a musical.

“What I’m finding with this is that it is definitely a play with music and wonderful music at that,” she said. “There are some very wonderful, uplifting numbers in the piece but at its heart there is this woman who is adamant that her girl is going to be a star,

“Every time you go back to a scene you go ‘that’s so clever’. Even though I thought I knew the show well I’m now seeing it in completely different light.”

For Ria that is partly due to the special setting of the Royal Exchange.

“What is unique in this production is that it is in the round which is thrilling for both the audience and the performers,” she said.

Although she is no stranger to Manchester - she brought Sunset Boulevard to the city earlier this year - Ria has never performed at the Royal Exchange before.

“I’ve always wanted to perform here,” she said, “and I’ve always wanted to play Mama Rose. I always hoped that would happen when the time was right and now, for me, it’s a perfect fit really – it works with my schedule, with my age (she’s now 52) and also with this gorgeous theatre.”

Ria had always cherished the dream that one day she would play Mama Rose.

“It’s funny,” she said. “I did an interview when I was in Paris earlier this year with Guys and Dolls and they asked if I could choose one role, what would it be?

“I said there weren’t many that I’d not done or were for the older women – there was Mame which has just been done, Dolly which I’d love to do but I said the main one would be Gypsy little knowing that months later I’d be there. It’s a big, big tick.”

Having spent 30 years at the forefront of the musical theatre, Ria admits she didn’t appreciate how fortunate she was to get such a big break when she was young.

“I think I’ve only realised that over the last 10 years or so,” she said. “When you’re 19 you don’t think how big a show is, you just get on with it. Now I wonder how I managed to play Evita at 19.”

Ria is visibly excited to be bringing Gypsy to Manchester for the first time.

“Oh, this is special,” she said. “For me it really is the gift that just keeps on giving. When I heard that Exchange was going to put it on I just wanted to be seen for the part. I was like’ get me an audition’. Now I just want as many people as possible to see this - for me it’s musical theatre heaven.”

Gypsy, Royal Exchange Manchester, until February 1. Details from www.royalexchange.co.uk