New research suggests Bradford will need to build even more homes over and above a 50,000 Government target.

However, leading Bradford councillors have expressed doubts about the study.

Last year the regional housing plan called for 54,840 homes - either new-build or conversion - by 2026 in the district. This would require 2,700 homes a year to meet demand from a growing population.

These figures are based on population predictions made in 2004, but research for the Yorkshire and Hum-ber Assembly is based on migration patterns in 2006 following the expansions in the European Union.

It suggests that over the 20-year period that the Regional Spatial Strategy, or Yorkshire and Humber Plan, operates, population levels will increase by 26 per cent, not 22 per cent, taking the district's population to 621,900 and would require 62,700 new homes over 20 years.

The report also indicates that in the last two years 11,100 immigrants have moved to Bradford and applied for a National Insurance number allowing them to work, figures which have been taken account of in the research.

Councillor Anne Hawkesworth, Bradford Council's executive member for environment and culture, has already spoken out against the current figures, which are due to become law in March.

After hearing about the Assembly's research suggesting Bradford would be hit with even more homes, she said: "There are already fears about the green belt being eroded. But any decision taken on these figures would be a knee-jerk reaction and irresponsible. They are assuming the increases in population of recent years will continue - it must be based on a short-sighted view. If the Government comes forward with even higher housing target figures based on this research it will beggar belief."

Labour group leader Councillor Ian Greenwood said: "No one can predict precisely what the long-term pattern or effect of migration will be and the report acknowledges this.

"New housing inevitably places pressure on land. Brown-field sites must take priority but there is a clear difference between developing marginal green-field sites that have been little used for years and concreting over the countryside. It is irresponsible to pretend otherwise. We should also recognise the importance of preserving open space in urban as well as rural areas."

Liberal Democrat group leader Coun Jeanette Sunderland said: "I don't know how local councils like Bradford can be expected to plan sensibly for housing development if the goal-posts keep moving. As things stand, people feel threatened by proposals about huge numbers of houses when they need to be reassured that their precious green spaces won't be gobbled up by developers, building whatever they can get planning permission for."