Massive expansion along the M11 corridor is threatening the lifestyle of people already living in Herefordshire and Cambridgeshire, said Essex and Hertfordshire councillors yesterday.

Half a million new homes planned for the area were approved at a meeting yesterday by the eastern regional assembly, despite Essex and Hertfordshire councils' belief that the counties' infrastructure could not cope with the additions.

The Guardian newspaper reported today that the decision was made under pressure from the planning minister, Lord Rooker, who insisted that the area between London and Cambridge was "a growth corridor".

Hertfordshire county councillor, Derrick Ashley said, “Roads, rail links, hospitals and schools are already overstretched, yet there are no plans for the government to address these issues.” He pointed out that the M25, M11 and M1 were already overcrowded, as were the rail links to London.

Although called the M11 growth area, in fact the plans are now for expansion in areas far from the originally allocated corridor along the M11. Affected areas are in Peterborough, Cambridgeshire, north Hertfordshire including Stevenage, and Essex. At the meeting yesterday some 478,000 of the new properties were allocated to these areas with land still to be found for 18,000 more.

Some existing towns such as Harlow will have to expand dramatically and at least two new towns will have to be built from scratch on greenfield land within the next 20 years.

Essex and Hertfordshire councillors had alternative proposals with fewer homes turned down at yesterday’s meeting. Derrick Ashley said: "Decisions about the future of Hertfordshire are being made by an unelected body that does not properly represent the people of Hertfordshire."

"The assembly has rushed into making decisions without a proper assessment of the true environmental impact and infrastructure requirements, not to mention the added pressure that the expansion of Stansted and Luton airports will have on our already overburdened road and rail network."