New Zealand's foreign minister, Winston Peters, has stood down.

Mr Peters is under investigation over undeclared political donations to his New Zealand first party.

Prime Minister Helen Clark has been under immense pressure to sack Mr Peters, and the pair met earlier in the day to discuss his future.

"It's very clear to me, and very clear to him that the appropriate thing is for him to stand aside from his portfolios and Mr Peters is offering his total cooperation, as you would expect," she said.

Ms Clark says she hopes the matter can be resolved quickly.

In the meantime, she will take over Mr Peters' ministerial responsibilities.

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