Judith Collins has promoted Michael Woodhouse to be her finance spokesman after Simon Bridges rejected the position because of Collins' plan to split the usual finance portfolio into two roles.

Collins has this afternoon unveiled her caucus reshuffle flanked by Woodhouse, new deputy leader Shane Reti and new number 5 Louise Upston. The top 10 consists of seven men and three women.

It has seen Bridges kept down the rankings, Andrew Bayly put at number 3 and former leader Todd Muller number 19.

Bayley, a Collins loyalist and chartered accountant, will be the shadow treasurer and take on the infrastructure and statistics portfolios. Collins said the role was similar to the arrangement in Australia and he would work closely with Woodhouse in finance.

She they would "be a powerhouse in my opinion".

It is understood Bridges was initially offered the finance role, but turned it down because he did not think Collins' decision to split the portfolio into two roles would work.

The move has cost him a spot in the top five with Collins ranking him at number 7 and giving him justice, water, Pike River re-entry and Maori-Crown relations.

When asked why Bridges wasn't given foreign affairs, Collins said: "These are decisions that I make". She refused to discuss whether she offered Bridges finance.

Former finance spokesman Paul Goldsmith has been given education and has dropped down the rankings to number 12.

The finance portfolio has been held by Paul Goldsmith but it is thought he lost it after the $4 billion "fiscal hole" error in National's plan during the election campaign.

Collins said Goldsmith was "absolutely very keen" to get into education, when asked why he was only given one portfolio.

Muller has also dropped down the list and has been given trade and export growth and internal affairs.

As well as finance, Woodhouse has been given transport and is deputy shadow leader of the House.

Louise Upston has held onto social development and is number 5.

Collins has taken National Security and Intelligence, pacific peoples as well as technology while deputy Shane Reti will retain health and will take on the children portfolio.

Mark Mitchell has been ranked number 13 and will hold the public service, SOEs and sports and recreation portfolios.

Collins said all of the new five MPs were all given a role and they were given a chance to show what they could do and she had to treat them all equally, when asked about former Air NZ boss Christopher Luxon.

She said "I hope so" when asked whether she thought the reshuffle had cauterised the dissent in the caucus.

MPs react

Bayley said he had a "great deal of respect" for Finance Minister Grant Robertson and it was "part of the job" to go up against him in the House.

Collins said Nicola Willis, now number 16, was very capable in the housing portfolio and said in order for people to go up in the rankings, some people had to go down and said both she and Willis weren't that concerned about the rankings.

Reti said the children portfolio would look at Oranga Tamariki.

Upston said a big part of the focus of social investment would be how to get more New Zealanders get back into work - not raising benefits.

Split role

The Herald's Claire Trevett revealed this week that Collins was considering carving up the finance role between former leader Bridges and Andrew Bayley.

The arrangement was likely to be loosely modelled on the Treasurer and Finance Minister split which is used in Australia, and had a brief appearance in New Zealand during the National/NZ First government of 1996 when Bill Birch was Minister of Finance and Winston Peters was Treasurer.

Typically, the Treasurer is responsible for overall fiscal policy while the Finance Minister is in charge of matters such as tax and revenue.

Collins was tight-lipped about the reshuffle yesterday after being re-elected as leader, with Reti installed as deputy.

She would only confirm Reti would be keeping the health portfolio but said she would be looking to reward "talent, hard work and loyalty to the party" and promised it would be "surprising".

After National's disastrous election result, which saw it win just 25.6 per cent of the vote, the size of the party's caucus was dramatically reduced from 55 MPs last term to just 33 this time.