The drive to build the homes is a key policy of the the Office of the Deputy Prime Minister. An ODPM spokesperson said that the timing of the Budget and legislative time cleared for debate on the war meant that the report stage on the bill to the House of Commons would not now be heard until after the Easter recess.
The bill would then go to the House of Lords, where it would be delayed once again, as many amendments can be expected, taking it beyond the summer recess.
If the Lords' amendments were then debated once again in the Commons there would be further delay. This would put the bill at risk of failing to hit the deadline for new legislation in mid-November.
If this occurred, the bill would have to be reintroduced in the next parliamentary session.
Any delay to new legislation would add to the delay of delivery of new homes
House Builders Federation spokesperson
A source close to the ODPM said: "This raises the question, if it runs into difficulties at the Lords stage, of whether it will get through this year."
Baroness Nicol, for one, is believed to have voiced concerns at a National Trust/Council for the Protection of Rural England seminar earlier this year that the bill's intention to get rid of county plans would undermine the planning process.
Roger Humber, a former chief executive of the HBF, said: "Ministers have told people that a significant number of amendments could be brought forward. Obviously Iraq could be throwing things off kilter, but unless major demands are made on parliamentary time in the next seven to eight months, I cannot see why it won't get through in time."