Labour leader David Cunliffe told NewstalkZB in April that he would be happy to debate Prime Minister John Key "anytime, any place, anywhere, I'll even do it on Mike Hosking's show."
NewstalkZB has posted the clip from an interview with host Tim Fookes which followed Mr Key's challenge to Mr Cunliffe for a televised debate on housing affordability.
After Mr Cunliffe agreed to the challenge, Mr Key retracted it saying he had been referring to the usual TV debates during the election campaign rather than a special one-off.
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Mr Cunliffe's comment was made in that context rather than in relation to an election debate.