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There are a few simple rules to living a long life. By exercising, eating healthy and curbing drinking and smoking, you might be able to add a few more years to your life.

It's a bit different if you are a cat. Millie, the 31-year-old feline, has become the world's oldest cat through a diet of bottled water, salmon, prawns, chicken and tuna.

Leslie Greenhough, 71, believes his tortoiseshell cat is the oldest living kitty in the world: Millie is 146 in human years.

The cat was first owned by Leslie's late wife, Paula, who first got her as a kitten at three months old.

Leslie puts down his cat's incredible lifespan to feeding her only Buxton mineral water, simple fish and meat alongside 'lots of treats' including 'cuddles on the sofa'.

The now retired purchasing manager from Stockport, Greater Manchester, celebrated her birthday earlier this year in March, treating her to a bowl full of chicken.

Recent heatwaves in Britain affected Millie like many millions of other Britons. Leslie said Millie has two fans on her at all times to keep her cool in the heat.

He added that he had been putting ice cubes in water and blowing the fans in her direction.

Leslie Greenhough, 71, believes his tortoiseshell cat is the oldest living kitty in the world - Millie is 146 in human years, pictured last her for the cat's 30th birthday

Millie, the 31 year old feline, has become the world's oldest cat through a diet of bottled water, salmon, prawns, chicken and tuna

Leslie said: 'I am very proud she has made it to 31, she is a real trooper.

'I have been feeding her mineral water for the past 10 years now.

'Nearby to our house work was being done to the water pipes, and because I am old I was classed as a vulnerable person.

'So they began dropping off Buxton water at my doorstep which I drank and also gave to Millie.

'When I turned my taps back on afterwards, dirty water came out, so I chose to stick with the Buxton which I have stuck with ever since.

'But I'm proud of Millie mainly for my wife really, she would be amazed with how well she is doing.

'Millie is around 146 in human years, I think that says it all really.

'Imagine being 146-years-old, I can't - it is only animals like tortoises that live to daft ages like that.'

Leslie met his late wife, Paula, on dating site Plenty of Fish in 2012. He could overhear his wife's pet Millie meowing in the background of their phone calls.

The couple got engaged in 2013 on Valentine's Day and married in 2014.

Leslie had owned a cat once before as a child, named Blackie, but hadn't had a pet in several decades, until meeting Millie.

Leslie puts down his cat's incredible lifespan to feeding her only Buxton mineral water, simple fish and meat alongside 'lots of treats' including 'cuddles on the sofa'

He said: 'Blackie used to follow me everywhere she was born in a paper mill and such a sweet thing.

'Millie was such a sweet cat when I first met her.

'Over the years Millie was bullied by other cats in the her neighbourhood, so she stopped going out and became more of an indoor cat.

'She's developed a cautious attitude - she's very shy.

'I think that's helped her live longer.'

Paula died six years ago in 2020 after contracting Covid-19, leaving behind Millie.

The cat struggled to eat after losing Paula.

Leslie said: 'It was incredibly difficult on both of us.

'Millie and I had bonded before she died, she would sit on my lap and my wife said she could see how much the cat loved me.

Recent heatwaves in Britain affected Millie like many millions of other Britons

To celebrate three decades, Leslie decided to a get a cake made with Millie's face on complete with 30 candles

'I think Millie knew my wife wasn't well.

'Millie wouldn't eat anything at first, I used to give her prawns and chicken, but over time she's back to eating cat food.'

Leslie said that it was his 'life ambition' to get her in the Guinness Book of records as the world's oldest cat - but that he can't prove her age.

He said: 'Unfortunately, the only person who can do that is my late wife.'

The only item of proof he has is a picture taken in 1995 of Millie eating out of a bowl.

The retiree also says Millie's personality has changed with her age with her now more 'relaxed'.

Millie starts a normal day by 'messing' about with Leslie before jumping to sit on the back of the sofa in the sun.

The cat lover said: 'She keeps herself to herself, she will wake up around dinner time and I will mess about with her with for 30 minutes.

'She only drinks Buxton water and has a diet of salmon, prawns, chicken and tuna.

'Millie likes to do her own thing, I will find her either asleep behind the sofa or asleep in my bed.

'Sometimes she will play out in the garden - a cat is a cat really.'