NZTA has made a further advance payment of $5 million to buy time while contractual negotiations over Wellington's Transmission Gully continue behind the scenes.
The money comes on top of an advanced interim payment of $14 million agreed in May this year.
NZTA announced this morning the current six-week winter construction programme for the billion-dollar motorway will be extended by a further four weeks.
This is while the Transport Agency continues to negotiate the full cost of the impacts of the Covid-19 shutdown and agree a new completion date for the project with the contractor and builder.
The 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.
The Transport Agency said the extra $5m was to cover the costs of the Covid-19 work shutdown and to enable the four-week extension of the winter works programme.
Both the $14m and the $5m payments will form part of any final settlement agreement.
Services general manager Brett Gliddon said NZTA was committed to seeing the road open at the earliest possible date.
"The extension of the winter works programme while negotiations continue will help minimise further delays.
"Waka Kotahi must take a considered approach to making any decisions that involve tax payer money and that is why an agreement on the new opening date and associated costs is taking time."
Gliddon said it was not appropriate for NZTA to make further comment on these issues until negotiations were completed.
"We understand the public interest in Transmission Gully and we will announce the new agreed completion date and further information when negotiations are complete."
Road Transport Forum chief executive Nick Leggett said he viewed the extra $5 million as money to keep the current relationship with the road builder going.
"This is about preventing a stop work and a complete collapse of the relationship with the road building contractors.
"Whatever configuration arises out of whatever they agree, this road is going to be severely delayed and that's going to mean costs for Wellington road users, the entire Wellington economy, and a loss of productivity and significantly compromised safety for road users."
The 27km road was facing problems well before the Covid-19 pandemic landed.
In February it was revealed the cost of the project blew out to more than $1 billion after NZTA agreed to pay the contractor another $190.6m in a settlement over delays caused by the 2016 Kaikoura earthquake, and flooding around the same time.
Earlier this month Transport Minister Phil Twyford 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.
Twyford subsequently confirmed to the Herald he did not believe the rumours to be true based on the advice he has received.