The Department of Transport has confirmed that an official study looking at ways of improving the A47 through Norfolk will also consider the A12 between Great Yarmouth and Lowestoft.
The study is one of six previously announced in the 2013 Spending Round, with the aim of identifying solutions to long-standing road problem hotspots across the country.
Transport Minister Robert Goodwill said: "Good quality roads don't just reduce congestion and improve safety, they boost the economy by unlocking growth. That's why we are spending up to £50 billion over the next 15 years on upgrading the road network.
"The A47 and A12 are vital roads that give motorists and businesses access through the East of England and I want to ensure both provide the best service possible. These studies will ensure that investment will be targeted where it's most needed."
Transport Minister Robert Goodwill has written to local authorities, local enterprise partnerships and MPs whose constituencies lie within the proposed geographic scope of the study to set out a brief synopsis of the proposals for the study. Arrangements have been put in place to discuss the details of the proposed scope of the study work with stakeholders during January and February.