AAA rating seen as a must-have

Incoming Treasurer Mike Nahan needs to set out a plan in May's State Budget to win back WA's AAA credit rating, the new chief executive of the WA Chamber of Commerce and Industry says.

Deidre Willmott, in her first interview since taking over last week, said the WA Government must conduct rigorous, transparent economic analysis around its infrastructure program to ensure it picked the congestion-busting projects that would deliver the biggest productivity improvements for business and the community.

She said engaging in debates about the Government's economic policy direction was part of the chamber's "core business". But she was unlikely to be a firebrand critic.

"We will always call it as we see it and if we have concerns we will be open about that," Ms Willmott said. "We will also be very careful to have these discussions as a direct dialogue.

"We won't necessarily be outspoken before we've sat down with decision-makers and had the discussion."

Ms Willmott has a long professional association with the Premier she predicted would help her do her job.

In 2008 she was the Liberals' endorsed candidate to replace Colin Barnett in his Cottesloe seat after he planned to retire but stood aside when the party asked him to lead it at the eleventh hour after Alan Carpenter called a snap election.

Ms Willmott was then Mr Barnett's chief of staff before taking executive roles at Fortescue Metals Group and for lobbying and communications outfit Cannings Purple.

She has returned to the chamber where she was executive director from 2006 to 2008.

Ms Willmott said Perth's livability was a priority because it was critical to attracting talent and retaining young people.

She hailed Labor's liquor reforms and the Barnett Government's retail trading changes for increasing vibrancy but said more work was needed.

Ms Willmott said this Budget would be among this Government's most important.

The CCI advocates asset sales and a greater role for the private sector in service delivery and infrastructure. It also wants a focus on a pathway to retain the AAA credit rating.

"What we've seen over the last few years is Budgets consistently estimate expenditure growth of 3 or 4 per cent and it's coming in at least double that each year," she said. "We all understand why, but we also understand it is not sustainable."

Ms Willmott said the Government needed to quantify the benefits of proposed infrastructure to make sure they delivered maximum returns.

"These aren't 'nice-to-haves'," she said. "These are the investments that will increase productivity."