Developer Larkfleet Homes will mount a legal challenge against the building of the southern bypass in Grantham in the Court of Appeal on July 23.
Larkfleet says that an environmental assessment of the road did not take into account the environmental impact of the housing development planned for the southern quadrant, off Somerby Hill.
A Larkfleet spokesman said: “This is key because the EIA for the housing development may identify significant environmental effects that need to be addressed but it will be too late to do anything about them because the planning permission for the road will already be in place and, indeed, the construction of the road will have begun.”
Larkfleet wants to build 550 homes on the other side of town at Manthorpe. Work on the relief road, linking the A1 with the A52, is due to go ahead at the end of August.