The National Roads and Motorists' Association has implored the Morrison government to back the state's request to fast-track the M1 Pacific Motorway extension.
NSW Treasurer Dominic Perrottet has listed the long-awaited link as one of four infrastructure projects the state would like to bring forward if the federal government fast-tracked funding.
Federal Treasurer Josh Frydenberg last week called on his state counterparts to nominate projects the government could fund to help stimulate the economy.
The extension, a $2 billion project that would link the M1 at Black Hill to the Pacific Highway at Raymond Terrace, has been on the cards for years.
The federal government pledged $1.6 billion to the project in April, but forward estimates showed the bulk of the funds would not be spent until 2023-28.
NRMA spokesman Peter Khoury said on Sunday that was far too long to wait for a "vital missing link".
"This is one of those vital missing links that has to be built," he said.
"When you consider some of the priority projects that exist around the state, for it to make the top four is a pretty good reflection of how important it is."
Mr Khoury said bringing the project forward would deliver a string of benefits.
"It's one of those projects that delivers a trifecta in value," he said.
"Obviously it improves congestion and safety, but also the delivery of goods and services - it makes the delivery of freight more efficient.
"It also makes it easier to access regional areas for tourism purposes and that is one of the strongest ways to improve regional communities."
Multiple upgrades to the Pacific Highway on the North Coast are nearing completion, and Mr Khoury said the M1 extension was one of the last pieces to the puzzle of the Sydney to Brisbane route.
"We had to upgrade the Pacific Highway, obviously, that was the number one priority in Australia over a number of years," he said.
"We're pretty much done. The only thing left to do are a couple of patches plus the Coffs Harbour bypass.
"So this is the next step. It makes the connection right up the coast significantly improved.
"You don't get the full benefits of upgrading the M1 unless you deal with this bottleneck."
Federal Labor matched the $1.6 billion commitment to the extension in April, with the party's then transport spokesman Anthony Albanese declaring he wanted to "advance" the project sooner than the government.
Newcastle federal MP Sharon Claydon said on Sunday the extension was one of "many competing infrastructure projects for the region", but fast-tracking it would be "a great opportunity".
"We know the difference the Hunter Expressway made when it was put in," she said.
"I also implore the government to back projects around high-speed rail between cities in Australia."