Political talk may actually turn into action, on the question of MPs' pay.

Politicians have this year been delivered raises starting at $8000 a year, all the way up to a $24,000 boost for the Prime Minister.

John Key says he's raising the problem with the Remuneration Authority, and would even back a law change.

"I don't think its actually sustainable every single year for an independent authority to be running increases which are broadly running above the national average."

Meanwhile, Andrew Little says the remuneration system for MPs is broken, and he wants to see it fixed.

The Labour leader - and all other politicians - are about to get a 5.5 percent pay rise, backdated to July.

But Little says the current system, which rewards MPs based on comparable salaries among corporate executives, doesn't work.

"Having been a chief executive of an NGO in the private sector. It's different - it's totally different and it has demands that you don't get in other jobs."

Little says donating the pay rise, or giving it back, doesn't solve the problem in the long term.

Meanwhile Prime Minister John Key doesn't know what he'll do with his $24,000 pay rise.

The multi millionaire says he donates some of his $450,000 a year salary to charity.

"Not all of it, I don't have a fixed or firm thing. I pay my taxes, I pay expenses that are incurred as part of my job, more so than other Prime Ministers would, and I make donations, but it's my private right."