How can wolf whistling be offensive to women? It’s a compliment,” says velvet-voiced Joanna Lumley, stoutly.

The morning we speak there’s a report in the news about the pet names and casual sexism which offend women. And Joanna’s having none of it.

“They’re saying ‘Cor you look all right, darlin.’ What’s wrong with that?”

One-time model, presenter, campaigner, actress – most recently reprising Ab Fab’s fabulous Patsy Stone for the big-screen – Joanna, OBE, is far from a saccharine “sweetie darling”.

This is a practical, no-nonsense lady who sugar-coats nothing. In the 60s, when she was a young model, people were made of sterner stuff, she insists.

(Image: James Vellacott)

“We were tougher in those days. You knew someone would whistle in the street and you weren’t insulted.

"We have become more sensitive flowers nowadays, people are very offended by everything.

“When I was modelling photographers were much ruder, they’d say ‘You look frightful, what’s the matter with you?’ ‘You look podgy, you look fat as a pig’.

“It was good-natured banter, you kind of got on with it, it didn’t upset you.”

At 70 Joanna has reached the status we like to term National Treasure.

“I adore it, it’s the kindest thing in the world,” she says silkily of the description.

Then, quick as a flash: “It just means people are used to you, and you have been around a long time.”

Joanna enjoys life. And few jobs are more enjoyable than playing drunken, drug-addled Patsy Stone.

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“It is always fun to go back to those ridiculous people,” she says.

And after the success of this summer’s Ab Fab movie, will she be returning again to that lopsided, bird nest of a wig anytime soon?

“That is up to Jennifer,” she says. “I think if she wrote it we would all go ‘Yay’ but she is the one to decide.”

(Image: BBC)

But there’s plenty of other things to keep Joanna busy. Although enjoying a long, happy marriage to musician husband Stephen Barlow – her first was to writer Jeremy Lloyd – she is often away.

“I’m about to start a film, then do another documentary in India, then another film, then a sitcom,” she says.

But she has always been busy.

Born in India to British parents, her father was in the British India Army, she went to boarding school in Kent. And she was desperate to get out into the world.

(Image: BBC)

“I couldn’t have taken being at university for three years, or drama school, I just wanted to be doing it,” she says.

Looking at stunning photos of lithe Lumley modelling for legendary fashion designer Jean Muir – the very first designer she worked for as a house model aged 17 – it’s hard to believe any one has ever called her a fat pig.

She looks back on those days with affection – although says she was always desperate to be an actress at heart.

It was her second job – her first was as an in-shop model in the London ­department store Debenham and ­Freebody.

(Image: Getty)

She was with Muir for three months before heading back to London in 1964 to work as a photographic model and it was far from captivating.

“A house model is completely not glamorous, it’s a living clothes horse,” she explains.

“I was of no importance, I was a body, no room for vanity. You didn’t have a name, models nowadays who have names and go about and don’t get out of bed for 10 thousand or whatever it is, that wasn’t the case then.

(Image: Getty)

“The fees were usually £5 an hour, even the tippy top models might have got 200 quid a day. People weren’t so mercenary or so self-obsessed.”

She recalls: “The rock groups used to walk around, be in the streets and catch taxis.

"It was less grand, everyone was much less grand, this Kardashian thing didn’t exist.”

“There was no social media, nobody took photos in nightclubs. It was much less self-conscious – now everyone’s self-conscious, they send out pictures of what they look like, what they like, what they think, even their food.

(Image: Getty)

“It was much more fun, it was freer.”

We may see Joanna Lumley as a star but she compares what she does to a very unlikely profession.

“We’re just like painter and decorators,” she shrugs.

“We adapt. If someone says ‘Will you paint my room purple?’ you go ‘Of course’ and do the best you can. We are not special.”

(Image: PA)

In the late 60s she made her name in acting, appearing as a Bond girl in On Her Majesty’s Secret Service, and later in the 70s, as Purdey in The New Avengers.

But first she learnt her trade in theatre, where, in her very first job, she suffered “a sort of nervous breakdown”.

Stern stuff she may be but, at that point, perhaps because she was on the brink of her dream, things got to her – working hard, raising her son Jamie as a single mum (she was no longer in a relationship with his father photographer Michael Claydon).

(Image: Rex)

“I had been in it for 10 months and it overwhelmed me,” she says.

“Everything combined to make life seem intolerable.” She had six months off, went home, and recovered.

She says she learnt not to be so affected. “If things are frightening, work out why and what you can do to stop being frightened by it.”

This mantra has served her well. “Illness doesn’t worry me because I’m not ill, I’m not an ill kind of person, I don’t get ill,” she says.

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She puts that, and her svelte figure, down to keeping busy, mainly.

“I don’t do anything,” she explains, referring to exercise.

“But I’m a ­vegetarian, which I think probably helps, and I rush about. I walk to the tube and rush up and down stairs and garden.”

Her advancing years simply aren’t a concern.

(Image: FilmMagic)

Her fearlessness in the face of ageing was shown by taking the role in sitcom Jam and Jerusalem as Delilah Stagg, an elderly church organist who nearly chokes on her false teeth.

Not even the loss of friends – she read a poem in Westminster Abbey at Sir Terry Wogan’s memorial service – strikes fear. There is, she says matter-of-factly, not much you can do in the face of old age.

“There is nothing tragic about death, death is what we all have for us. If you’re born you are going to die, darling. Don’t get too thingy about it.”

Darling, I can’t imagine her getting “thingy” about anything.