BECOMING the worst singer in the world is more testing than even Simon Cowell imagined... you nearly lose your voice after two performances in a day for a start.

Maureen Lipman kindly agrees to an interview in just such a state to discuss her role as the American "dire diva of din" Florence Foster Jenkins in a new play by Peter Quilter, which plays Newcastle's Theatre Royal next week.

Called Glorious, it tells the true story of a delusional singer in the 1930s and 40s who made records and, famously, sold out the Carnegie Hall.

Joking about her croaky voice, Lipman says: "Well, I have just got to learn to do eight shows a week. No actress on earth would have agreed to do that, but that was simply because I'm a silly cow and never think ahead. If I'd had anything about me I'd have said to the producer that it was impossible. I only had to play Joyce Grenfell seven times a week, so this is an absolute deathwish, but I'm stuck with it.

"I have got a mike for the singing parts, so I don't have to shatter my larynx. The trouble is that I get a couple of laughs and then go for it," she explains.

Lipman's wicked sense of humour is clearly returning after her period of mourning for her late husband, the playwright Jack Rosenthal, who died in 2004. Even so, she admits it wasn't easy playing Florence Foster Jenkins for a gala performance of Glorious dedicated to Rosenthal's Multiple Myeloma (cancer of the bone marrow) Memorial Fund.

On the prospect of being without Rosenthal for her 60th brithday next year, she says: "I spent my first holiday alone this year on a Greek island. It was wonderful and at the age of 59 I'm slowly, slowly being dragged to the realisation that I'm a grown-up, having been unconvinced of this for a very long time. It's taken me two years to realise that this is not a part I play and he's not coming back and I have to become much tougher and more responsible than I was for the rest of my life. So next year I hope to ship a party out to the island of Zakynthos to a caf bar, where I spent most of my time, giving them a bloody good week.

"I'm so surrounded by friends and heartbreak and I don't think that's just because I'm coming up to the big bus pass. There's a proliferation of cancer among those I know so that now one lives simply day to day."

A tour and possible West End run of Glorious may change all that for the woman recently included in Britain's top ten funniest women. The success of playing Florence probably rests with the way audiences in this country love eccentrics and heroic failure.

Lipman observes: "I must say, I do love her, she's just the most eccentric character and the thing is about eccentrics is that they are happy people who don't care what the world thinks about them. That's why we've loved Magnus Pyke, David Bellamy, Margaret Rutherford, Barbara Wodehouse or even that nun with the teeth who talked to us about art. We relish them because they don't care for convention but, inevitably, they start to parody themselves and fizzle out."

Describing Florence at the height of her success in the Carnegie Hall, Lipman says: "People were being carried out banging their heads on the floor, but she only heard the applause and the real die-hard aficionados who always went actually turned the laughter into cheers and applause. Then a month later she died and there is one school of thought that she died of a broken heart but the reviews were pretty kind. I think she just peaked and burnt herself out at the age of 70-something."

Lipman is aware that there's an American version of the 'socialite soprano' story in New York at the moment starring the singer Judy Kaye. "They're pretty pissed off about our version, but our playwright Peter Quilter is such a sweet man who re-writes at the drop of a hat daily," she says.

Quilter has had a huge success in Australia with the play about Judy Garland, The Other Side Of The Rainbow, which has already been snapped up for Broadway.

One obvious question is how are the critics going to review a performance based on bad singing? Lipman laughs. "Very well in the provinces and they're going to throw **** at me in London like they always do... What else is new?"

Whether we'll see another comedy vehicle on TV starring Lipman remains doubtful - "unless I write one myself, although I'm not quite old enough to play an amateur detective and I see myself more as a cranky patient than a doctor".

But she remains a favourite with UK audiences since the award-winning days as Beattie the archetypal Jewish mother in those 1980s BT commercials. "That's the great thing about this country. I can remain completely anonymous or people can be very nice when they do accost you. I've been in the industry since 1967 which is a long time, but I'm still here and it's all I know how to do."

l Glorious runs at Newcastle's Theatre Royal from Tuesday until Saturday. Box Office: 0870 905 5060