Next July, Bette Midler will play a string of gigs across the UK, her first here since 1980. A second date had to be added at the O2 after the first sold out, so why has she been away so long? Was it something we said?

“No, no, no,“ insists Bette, who is perched on a sofa in a plush London hotel suite. “I wanted to come, but I guess life interfered.“ To be fair, the artist, also known as The Divine Miss M – the title of her 1972 debut album – has been pretty busy.

As well as racking up a trio of Grammy Awards and selling more than 30 million records worldwide, she has proved her acting chops, starring in comedies like The First Wives Club and Hocus Pocus, not to mention the ultimate tearjerker Beaches, for which she also recorded her most famous ballad, Wind Beneath My Wings.

In terms of music and movie success, only Cher can really rival the Hawaii-born performer.

Bette hasn’t shied away from the stage, either. She completed a two-year stint of nightly live performances in Vegas in 2010, a time she looks back on as “the most beautiful show I ever did. That means a lot to me“.

Not that she misses the gruelling schedule.

“It was hard work,“ she recalls. “I had a little adrenal failure, where you just can’t get up every night. I was having a lot of Vitamin B12 shots to get through it.“ More recently, Miss M has been back in the studio, recording It’s The Girls!, an album of girl group covers. It’s an idea that she jokes has been “floating around since 1871 or something“.

Featuring ladies-only tracks from the ‘30s onwards, Bette says she wanted the production style to reflect the ‘60s girl group heyday.

“It was rough back in those days. The music had an immediacy because it wasn’t processed, and that’s part of the charm, selling the music to teenagers because they sounded like teenagers.“ So does the 69-year-old think her voice can cope with such a youthful sound?

“There are certain parts of my voice that sound very young. I never smoked like a real fiend, so I didn’t lose the top end of my voice. You can keep your high voice, but you have to look after yourself.

“I run on the treadmill. And it’s only for the pumps – I don’t care whether I’m thin or fat, but I care about whether the lungs are working to drive the voice.

“It’s like a car, you have to take care of it, clean those spark plugs, baby!“ she adds, laughing.

Whatever Bette’s doing, it’s clearly working; it’s hard to believe that the slender, 5ft 1in singer is heading for her eighth decade.

Nibbling on macadamia nuts and apricots during our chat, Bette tells me she keeps up with contemporary music too, and chose all the modern tracks on the album, like TLC’s Waterfalls, herself.

Right now, the universally adored star is focusing on the future and next year’s transatlantic tour.

“People here are real music fans. They like that I tell jokes on stage, they like the entertainment, but really they want a music show.

“And you Brits get the music hall element of it all. You have that old showbiz tradition. In the States, a lot of people think what I’m doing is brand new but it’s so very, very old.

“I’m grateful to come to a place where this all makes sense, without having to explain it.“ As usual for an artist of advanced years, rumour has it this will be Miss M’s farewell tour. Are the whispers true?

“I don’t know. Possibly,“ she admits. “I don’t know how wise it is to go on forever. If the spirit is willing and the flesh is strong, then go for it, but if something is holding you back you shouldn’t be chained to the idea that you can’t retire.

“There are people who come alive when they think about the possibilities of travelling in their retirement.“ One of those people is Bette herself, who talks animatedly about a trip to Mexico City last year.

“My whole life, people have been telling me not to go, that it’s polluted and filthy, but going there was the greatest thing that ever happened to me.

“It wasn’t the cleanest place I’ve ever been, it certainly has major problems with inequality, but there was a vibrancy there and the food was fantastic, and the art and the history are overwhelming.“ The trip was an eye-opener. Despite touring the globe for decades, Bette now realises she actually saw very little.

“I saw the inside of every hotel, a studio, and sound stages... but didn’t see anything.“ It sounds as though Bette quite fancies spending her dotage on a grown-up gap year, roaming the globe.

With such a serious case of the travel bug, it’s hard to imagine Bette returning to the stage after next summer.

A safe bet would be to snap up a ticket now, and catch The Divine Miss M while you still can.

It’s The Girls! is out now.

Bette Midler will be at the O2 Arena on Saturday, July 17 and Sunday, July 18, Peninsula Square, London SE10 0DX. Details: 020 8463 2000, bettemidler.com