Health Minister Simeon Brown was met with booing at the senior doctors' annual conference before accusing doctors of  "crossing an ethical line" and threatening compulsory arbitration. 

New Zealand First leader Winston Peters fired off some threats of his own suggesting regulation for Fonterra if the Lactalis sale proceeds. 

ACT leader David Seymour hit back at Peter's threats saying the decision is for the farmers, not the Government. 

Newstalk ZB senior political correspondent Barry Soper says 'politicking' tiffs like Peters and Seymour's will become more common as elections approach next year.

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