AAP, with a staff reporter
Opposition Leader Tony Abbott has committed to funding a $3 billion tunnel linking NSW's F3 and M2 motorways, as the state government nears a deal with the Gillard government to bankroll the project.
Federal central coast MP Craig Thomson confirmed reports that money for the 8km tunnel will be included in next week's budget.
Under the plan, both levels of government would invest up to $400 million, with the tunnel to be built from as early as next year.
The rest of the money would be provided by a private company that would recoup funds through a toll.
NSW roads minister Duncan Gay said the state government was close to striking a deal with federal Labor, saying discussions were "friendly and we're close but we're not there yet".
Mr Abbott weighed into the matter on Thursday, saying his government was committed to the four-year project, which links the F3 and M2 motorways in Sydney
"We will get this link built," he said,.
Mr Abbott will release the full details of the funding commitment prior to the next election.
NSW Treasurer Mike Baird said it was important not to overcommit the state.