The Let's Get Wellington Moving (LGWM) transport plan has spent $35 million on consultants since 2017.

Over the same period just $253,000 has been spent on construction for the multi-billion-dollar programme, which includes proposals for light rail from the city to Island Bay and a second Mt Victoria tunnel.

National's transport spokesman Simeon Brown said the Government has been getting Wellington consulting, not getting it moving.

"Instead of making consultants rich with endless talk fests and working groups, the Government needs to get on and deliver the transport projects Wellington needs such as the second Mt Victoria Tunnel."

New Zealand has about $65 billion worth of infrastructure projects planned over the next five years.

Over the next 30 years this is expected to grow by as much as $140 billion, according to the Infrastructure Commission's national infrastructure pipeline.

Te Waihanga infrastructure delivery general manager Blake Lepper said this was a significant increase in infrastructure investment and was creating capacity challenges across the sector.

"What we are hearing from the sector is that current market conditions are affecting the delivery of infrastructure.

"In some cases, infrastructure providers are struggling to find suitably qualified professional advisors they need to support the design, planning and procurement of the projects."

LGWM is the biggest investment in Wellington's transport in decades - up to $7.4 billion over 20 years. It is a joint programme between NZTA Waka Kotahi, Wellington City Council and Greater Wellington Regional Council.

Partnership board chairman Dave Brash said the transport plan was designed to be led by a lean core team supplemented by consultants with specialist expertise.

"We mostly use NZ consultants but go overseas where we need specialist expertise and advice not available here."

The types of consultants used range from those specialising in civil engineering, urban design, environmental planning, procurement, to modelling and economics, Brash said.

"It is currently a tight market for such expertise and consultants themselves are also limited, especially in specialist areas.

"There is also significant transport and urban development projects being undertaken in Australia and the UK for example, also competing for international talent."

Last week Wellington Airport launched a legal challenge against one of LGWM's first projects, which is the installation of a pedestrian crossing on State Highway 1.

Brown said this crossing, along with reduced speed limits on Cobham Drive, would just slow Wellington down.

Construction on any of LGWM's smaller projects has been slow to start and at the end of last year there were spades in the ground at all of two intersections.

"In early 2021, I was clear that the progress on LGWM was unsatisfactory, and that I wanted to see the project accelerate with initial physical works beginning by the end of the year", Wood said.

"While small, I was still happy to see the first physical works delivered in November 2021, with safety and accessibility improvements to pedestrians delivered at two intersections along Whitmore Street."

Wood said Wellingtonians could expect further construction on central city pedestrian improvements in the coming months, with other public transport service improvements following later this year.

Decisions on the preferred mass transit plan are also expected to be made within the next few months.