THE minister for “eco-towns” has conjured up an improbable argument to counter her critics: concrete is good for the countryside.

Caroline Flint, faced with mounting objections to government plans for 10 eco-towns on greenfield sites, said this weekend that turning fields into housing estates could improve the “green environment” and biodiversity.

She cites the 1960s-built “new town” of Milton Keynes, which is famous for its concrete cows and roundabouts, as evidence of how development is good for nature.

“Given that Milton Keynes was built on agricultural land, I’m sure there were people at the time who said, ‘This is terrible; we’re losing this green environment’,” she said. “What MK has shown is that you can actually enhance the green environment.

“That’s partly because they’ve actually managed the green space, growing the plants and developing the bird life and what have you, which has meant it’s far richer today than it was when it was just agricultural land.”

The claim that Milton Keynes, a town of 185,000 covering 34 square miles in Bedfordshire, is richer in green space than when it was fields, wins support from some officials, including Mike Street, conservation manager at Milton Keynes Parks Trust.

“It seems a surprising statement to make, but it’s one that Natural England recognise. In many cases developed areas can have a greater biodiversity than the greenfield sites that were there beforehand. And that is certainly the case in Milton Keynes,” he said.

“The urban environment now has a wider range of habitats and species than was there before Milton Keynes sprung up. It depends on the quality of the habitats that are going to be built on. In MK’s case, development has retained some of the habitats that were there previously whilst expanding and creating others.”

Try telling that to rural campaigners and villagers in Oxford-shire, Hampshire and Leicestershire who believe eco-towns on their doorsteps will destroy the countryside and quality of life.

“It’s like saying the London Zoo in Regent’s Park is much more biodiverse than what was there before,” said Neil Sinden, policy director of the Campaign to Protect Rural England. “There may be more species, but the overall level of natural habitat is drastically reduced.”

Rural campaigners are gearing up for a fierce battle as the government prepares to pick the sites for the new towns from a shortlist of 15.

Flint is unfazed. “We all live somewhere that was once a green field,” she said. “I’m not saying we’re going to please everybody, but it’s about being clear about why the development is necessary, and what safeguards there are going to be to ensure these eco-towns are going to be sustainable.

“In many respects, there could be benefits from these eco-towns in terms of public transport and affordable housing that couldn’t be realised another way.”

Will the new towns - or “Flint-grads” as critics have christened them - be places of beauty?

“Um . . . obviously beauty is in the eye of the beholder,” Flint said. “Certainly I would hope that design that people can live with will be very much an important factor in eco-towns.

“People have to feel comfortable in the places they are living and working.” She said there were “no ifs or buts” about respecting local planning processes and there would be no building on the greenbelt.

Would she like to live in one, then? “I’d never say no.” Though she now owns two properties - a flat in London, and a house in a village outside Doncaster - her first homes were humble.

The daughter of a teenage mother, who died at 45 of an illness linked to alcoholism, she was born in a home for unmarried mothers in north London. She grew up in cramped rented quarters before moving into council housing.

“My earliest memories were in a private rented flat which was very small. I recall we had one room where literally my sister and I slept on one side of the wardrobe and my parents on the other. Later on we had a private rented terraced house. Later on in life, we were in a council flat, so I’ve been through that.

“It was only when I got together with my husband that I got to own a home. It was my late twenties. My husband owned a home, in which he went through terrible negative equity, and together we got through that difficult time.”

Her personal experience may prove a good qualification for being a housing minister.

One of the shortlisted eco-towns is in her own constituency, Don Valley, while 12 of the remaining 14 are in Tory constituencies. That is a coincidence, she says, not a plot to dump the development on Labour’s opponents.

Though she will face a tough task persuading local people to accept the plans, Flint brings a rare mix of talents to the task.

Last week she displayed her cool on the local election campaign trail. Running late after a photocall with Gordon Brown, she almost missed the train from London to Milton Keynes, where she had a packed schedule. She came tearing down the platform, hair and handbag flying, in 5in heels. Forced to find a seat at the back of the train, she didn’t bat an eyelid as she drew wolf-whistles.

Widely regarded as one of Westminster’s most attractive politicians, she’s also known as the “Black Widow” by rivals who say she’ll step on anyone to climb the career ladder. Recently, Nadine Dorries, a Tory MP with a blog, accused her of behaving like a “fishwife” in a tearoom spat over abortion law.

For all Flint’s determination, the eco-town schemes may run into greater trouble than rural dissent. If the gloomiest economic forecasts are right, and thousands of households slide into negative equity, government plans for building between 160,000 and 240,000 homes by 2016 may come under pressure.

Later this month, Flint and Yvette Cooper, the chief secretary to the Treasury, will meet the Council of Mortgage Lenders to discuss options to stave off the spectre of repossessions.

Flint admits the situation is “very serious” for some families, but sticks firmly to the government line that the picture isn’t nearly as bad as it was in the early 1990s. She says the government is ready to explore “every option” to help those struggling to meet mortgage repayments.

Does she blame lenders for being too ready to dish out credit, or borrowers for overreaching themselves?

“I think we have a competitive market which has allowed a lot of people to get on to the housing ladder. If we hadn’t had that, people would have said ‘why are we being denied the opportunity to own our own home?’,” she said.

It’s the sort of politician’s answer that has got Flint to where she is today: well on the political ladder and hopeful of trading up.

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