Health Minister Dr Shane Reti could be sliding down the Cabinet ranking's in this afternoon's reshuffle

Prime Minister Chris Luxon's expected to unveil several major changes to his National Party lineup, shortly.

It's thought Dr Reti could be losing the Health portfolio - to Simeon Brown - as the Government grapples with the sector's deficits and governance issues.

Newstalk ZB's political editor Jason Walls says says Brown's proved he's good at towing the party lin, while delivering the results Luxon's seeking.

He says there's a few at the top like that - making up Luxon's core inner circle - like Brown, Nicola Willis and Chris Bishop.