A public inquiry into plans to widen the last remaining single carriageway section of the A11 between Norfolk and Suffolk has been adjourned.
Upgrading the section between the Thetford bypass and Fiveways Roundabout at Barton Mills could cost up to £147m.
The inquiry has now been adjourned until 25 January.
The main landowner, Elveden Estate, said it needed more time to consider a response from the Highways Agency about access routes.
The scheme also includes a bypass to take traffic away from Elveden, which has Conservation Area status.
The existing nine mile (15km) single-carriageway section is the only piece of non-dual carriageway between Norwich and London.
The inquiry began two weeks ago and was extended to this week to allow more time to hear the views of local people and Elveden Estate.
There are also 25 other objections, mainly concerning the Fiveways roundabout and whether it will be able to cope with the traffic flow.
Supporters of the scheme have told the inquiry how crashes could be prevented and half a billion pounds could be saved by businesses if the road's bottleneck is removed.
The road could open in early 2013 subject to the outcome of the public inquiry.