The warning from the Home Builders Federation comes as its latest Housing Pipeline report showed that planning permissions in the second quarter have returned to pre-crash levels.

But the headline growth in plot approvals hides the fact that individual housing schemes are struggling to get final sign off from councils.

Approvals for several larger schemes has significantly boosted English planning permissions to 56,647 homes in Q2.

This maintains the steady increase in total permissions granted in recent quarters taking the 12-month rolling figure to 197,325 permissions, a level not seen since 2008.

But house builders warn the actual number of schemes or sites coming through remains worryingly low.

Just 715 new sites were granted permission in the second quarter compared to over 1,000 per quarter in 2007/08.

Stewart Baseley, executive chairman of the HBF, said: “The increase in the overall number of new homes getting planning approval is very positive.

“Everyone is agreed that we need to dramatically increase house building to address our housing crisis and so getting more planning permissions is imperative.

But he warned: “The comparatively low number of actual sites getting permissions is concerning.

“We need to see work underway on more sites if the overall number of new homes being built is to continue to increase.

“In addition, too many sites with outline planning permission are now stuck in the planning system awaiting final permission to start on site.

“We estimate there could be as many as 150,000 plots across the country in such a position.”

He called on local authorities to ensure their planning departments are sufficiently resourced to process applications speedily.

Build and sales rates on bigger sites are similar to those on smaller sites, so to increase overall housing output, having work ongoing on more sites is imperative.

Doing so allows home builders to increase the number of sales outlets, maximise production and provide greater consumer choice.

Allan Wilén, economics director at Glenigan which supplies the data, said: “Strikingly approval figures have been boosted by a number of large scale redevelopment projects, such as the Earls Court scheme in London, which should provide a flow of new housing supply over the coming years.

“In contrast the drop in social housing projects is disappointing given the pressing need for more affordable housing.”