It's still a life of hard knocks for the south Wales Valleys, struggling to find a viable economic future in the wake of hundreds of years of exploitation and the more recent Tory-inspired decimation of steel and mining communities.

The Welsh industrial cause has not been well served by its home-based business sectors, which have failed to take proper advantage of billions of pounds in European funding for deprived regions such as the Valleys.

Last week Wales's biggest house-builder Persimmon Homes announced it was pulling out of one of the poorest of the Valleys - the reason being that it does not make enough money out of houses on sites north of Pontypridd in the area known as Heads of the Valleys.

The firm, which builds about 1,000 new homes annually in Wales, blamed low sales prices and heavier regulation by the Welsh government.

Regional managing director Glyn Mabey told reporters it was not "economically viable" to build there, while acknowledging that the decision would be detrimental to the area - both through direct and indirect job losses - and would mean "a decline" in an already depressed area.

Abedare housing agent Gavin Williams argues that Persimmon came a cropper for overpricing new builds.

"They have always been known to try to get above-market values but the market has not been there. Persimmon should have done their research."

But unlike much of Britain the valleys aren't desperate for new housing.

"We're not over-reliant on new builds," Williams says. "There's plenty of Victorian and post-war houses. There's not a shortfall. If the area was demanding it it would have an effect, but there's plenty of supply for demand."

Councillor Jeffrey Elliot, whose Cwmbach ward in Aberdare is scheduled to be where the last Persimmon-built scheme takes place, is less optimistic.

"Persimmon provides jobs and they provide nice, affordable housing in this area, and a lot of people are coming into this area as a result," he says.

The announcement came without warning - worrying since the Welsh Assembly government likes to boast that it works with businesses to see what help can be given to solve problems like this.

The stark announcement smacks of an attempt at blackmail - Persimmon has blamed planning regulations and environmental requirements that it says add £3,000 to the cost of building a house compared with England.

But only last year the government eased up on a tranche of environmental regulations in order to "help out" business. What's left are basic requirements such as wall and ceiling insulation, vital for energy conservation.

The Welsh government should seek to work with house-builders, but really it ought to get on with a house-building programme directly - and get Wales out of a housing blight that has lasted decades.