Phil Twyford has never visited Wellington's Transmission Gully site during his time as Transport Minister.
In response to an Official Information Act request, Twyford said he has received three invitations from the New Zealand Transport Agency to visit the site during this Government's term.
He accepted two of the invitations, the first of which was cancelled due to an "urgent matter" and the other was postponed due to the onset of Covid-19 and subsequent lockdown restrictions.
"As such, I have never visited the Transmission Gully site to date", Twyford said.
The troubled project has blown its budget, been bailed out by the NZTA, suffered significant delays and faced criticism for being run like a circus.
It's being built through a public-private partnership, the Wellington Gateway Partnership (WGP), with CPB Contractors and HEB Construction sub-contracted to carry out the design and construction.
Last week NZTA announced it was pouring another $14 million into the project, this time to the builder of Transmission Gully to reflect the costs of the Covid-19 work shutdown.
That $14m is an interim payment, which will form part of any final settlement agreement.
Earlier this year it was revealed the cost of the project blew out to more than $1 billion after NZTA agreed to pay the contractor $190.6m in a settlement over delays caused by the 2016 Kaikoura earthquake, and flooding around the same time.
National's Transport spokesman Chris Bishop said Twyford was on record saying governments have over-invested in roads and motorways for decades.
"So I guess you'd say he's living his values", Bishop said.
But he said it was negligent of Twyford to have never visited the site.
"It's an incredibly important project for Wellington and the region, in fact the whole country, and I would have thought he'd have been out there at least once in the last two and a half years he has been Transport Minister."
It was particularly disappointing in light of recent concerns over delays and escalating costs, Bishop said.
"He should take more of an active interest."
In a response to the Herald, Twyford said he has tried to visit the site, but unfortunately circumstances like Covid-19 hitting before his last planned visit meant he couldn't.
Twyford said roads were critical.
"That's why this Government is properly funding road maintenance, fully funding crucial roads like Otaki to North of Levin and Mill Rd, and upgrading over 3,000km of roads with safety upgrades.
"Compare this to the record of the last government – road maintenance expenditure flat-lined, ghost roads were promised with no funding and appalling road-safety statistics."
Road Transport Forum chief executive Nick Leggett said it was up to the Minister to prioritise his time.
"I would trust that he does that effectively", Leggett said.
"But it does surprise me that such an important infrastructure project that has run into quite serious problems has never been visited by the Minister of Transport."