New Delhi, Sept. 21 -- The National Highways Authority of India (NHAI) has introduced a uniform design framework for high-speed access-controlled national highways, seeking to standardize how such corridors are planned and designed as India expands its network of high-speed roads.

The guidelines, issued on Monday, apply to the upcoming four- and six-lane access-controlled greenfield and brownfield national highways, excluding expressways. They assume significance as the government targets the development of 50,000 km of access-controlled high-speed corridors under its Viksit Bharat 2047 road map.

Until now, there were no separate standards governing the planning and design of access-controlled high-speed national highways other than exp...