The Kings Highway in southern New South Wales is in desperate need of an upgrade, the NRMA has declared after two people died in a head-on smash near Braidwood yesterday.

The motoring group's president Alan Evans told the ABC this morning that state and territory governments - and the federal government - have failed to treat the road with the urgency it required.

"The highway is missing a number of things," he said.

"It doesn't have enough passing lanes, its road alignment in parts is not up to standard. There is a number of features when we've done an assessment of the road we believe demonstrated it is not a safe road, which is below standard - and of course the crash statistics bear that out."

The NSW government however says upgrade work is being done on the highway. A project to add overtaking lanes between Queanbeyan and Bungendore is expected to start later this year.