National leader Simon Bridges is accusing the Government of copying its infrastructure plans, saying ministers had no new ideas of their own.

But Prime Minister Jacinda Ardern says the Government's $12 billion infrastructure spend was necessary because while National was in Government, it sat on its hands when it came to funding key projects.

This morning the Government unveiled its much-anticipated infrastructure package.

Almost $7b was earmarked for transport projects in Auckland, Waikato, Bay of Plenty, Wellington, Canterbury and Queenstown.

Much of that will be spent on significant roading projects, including State Highway 1 from Whangārei to Port Marsden, Mill Rd in South Auckland and widening SH1 from Papakura to Drury.

The Tauranga Northern Link has also received funding, as has SH1 from Otaki to north of Levin.

Some $1.1b has been made available for rail projects.

Bridges said this morning's announcements show that after two and a half years, the Government has realised it has no new plans of its own.

He said the Government had: "copied the plans I put in place when I was Transport Minister".

"It's quite flattering, really. It's just a shame that an entire term of Government has been wasted by tearing up these plans and putting them back together again."

He was critical of the Government for taking two years to announce some serious infrastructure projects.

"The two-year pause on starting these roads has seen our construction workforce go overseas in search of work. We'll struggle to get them back now.

"This is a tragic wasted opportunity."

But senior ministers were this morning at pains to point out that under National, not enough was being done when it comes to infrastructure.

In fact, Ardern said the infrastructure package was: "better, faster and funded".

Ardern, and Finance Minister Grant Robertson, pointed out that National had talked about funding some of the projects, but had never allocated any money towards the roads.

Robertson said the Government's package "stands in stark contrast to what we have seen in the last nine years, where there was a lot of talk but not a lot of walk".

In fact, he said the "significant underspend" on infrastructure under National had been "a handbrake on the economy".

"This is a Government of infrastructure."

In December, after releasing its infrastructure policy document, Bridges referred to National as the "party of infrastructure".