Twyford spent a couple of hours this morning with contractors, workers and managers on the site of what he called a "spectacular piece of civil engineering".
"We drove a considerable stretch of the new highway. It's an amazingly challenging and complex piece of work for the contractors and I'm even more motivated than before to ensure that we get the current contractual negotiations completed so we get this road finished."
The billion-dollar road is 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.
Twyford has also put to bed rumours NZTA has been approaching other contractors to finish the job in the event the WGP folded.
In a response to a written question from National's Transport spokesman Chris Bishop, Twyford said he has been advised NZTA has not approached any other contractors to complete sections of Transmission Gully.
Today Twyford confirmed he doesn't believe the rumours to be true based on the advice he has received.
Transmission Gully has been plagued by delays and in May was handed a $14m lifeline from NZTA to reflect the cost of the Covid-19 lockdown. A final cost is still being negotiated.
This came after NZTA bailed out the contractor to the tune of $190m in a settlement over delays caused by the 2016 Kaikoura earthquake, and flooding around the same time.
One expert described that number as "astonishing" and suggested contractors were not taking the environment seriously.
Rumours are rife that the builder is threatening to walk away from the project in negotiations.
But at a recent select committee hearing NZTA board chairman Sir Brian Roche said until a decision is made on the negotiations, everything else is speculation.
"We are committed to getting the existing relationship to work. We don't have sole decision rights in that matter, we are reliant on the contractor taking a fair and reasonable approach to this but we can't deny the fact Covid has created time delays and it's created additional cost. We are working through both of those."
An Official Information Act request revealed that up until today, Twyford had never visited the Transmission Gully site as Transport Minister.
At the time he said he 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.