The High Court said the coalition acted unlawfully in axing Labour's home-building targets, called regional spatial strategies.
Landscape experts had attacked the replacement with tax sweeteners for councils to build houses as hasty and too weak to prompt the housing market's recovery. Cala Homes, which brought the court action, said last week planning needed "clarity and confidence". A new system would take time to implement and could lead to an interim policy vacuum.
Liz Peace, chief executive of the British Property Federation, said builders may use the ruling to challenge council decisions to reject housing schemes.
Communities secretary Eric Pickles responded: "Later this month we will introduce the localism bill to sweep away the last government's controversial regional strategies.
"Top-down targets do not build homes - they have just led to the lowest house-building rates since 1924. The coalition remains firmly resolved to scrap the last government's imposition of confusing and bureaucratic red tape."
Landscape Institute chief executive Alastair McCapra commented: "The court found the secretary of state could not arbitrarily set aside strategies without due process of law. In fact legislation will be put before parliament very shortly to correct this legal anomaly - so he will get his way in any case."
Meanwhile, housing minister Grant Shapps has given details of the £900m new homes bonus to replace spatial strategies (HW 3 September). The government will match council tax raised on all new homes built for six years. "The new homes bonus will ensure communities that go for growth reap the benefits of development, not just the costs," he said.