A plea for political consistency to guarantee major construction projects get completed

The cost of Auckland's City Rail Link has ballooned over the past decade, from 3.4 billion dollars to almost 5.5 billion.

Outgoing chief executive Sean Sweeney's called for a reset on infrastructure planning, amid concerns political bickering is the biggest factor driving up costs.

Infrastructure New Zealand chief executive Nick Leggett says at least some consensus on the project pipeline is needed.

He says Sweeney's a classic example of talent leaving New Zealand because there isn't a project pipeline that gives them confidence work is coming up.