New Zealand First leader Winston Peters says if his party is in a position to negotiate with both major parties after the 23 September election, he'd be aiming to tell the country which party they would work with by 12 October.
That is the same date as the return of writs for the election, marking the delivery of the final results to the Governor-General.
Mr Peters made the same promise to communicate a decision by writ day on 2005, and said he would do the same this election.
"If you're going on precedent, yeah, 2005 we had a decision by writ day and we expect the same would be the case if those circumstances arise in 2017."
The belief he held the country up for weeks after the 1996 election while negotiating a deal was exaggerated, Mr Peters said.
"1996 was totally different, it was our first MMP election, the first time we were dealing with circumstances never dealt with before in this country's history.
"Seven weeks in my view was the kind of period we needed to, when you're negotiating earnestly and sincerely with both sides it seemed to be an exercise we had no precedent for, and no record for."
Since then, he said, parties had become much more familiar with MMP and the way it works.
"So I fully expect, post the election, that every party would look at resolving this matter as fast as possible - that's all I can say."
Mr Peters said his party's main focus was on the next eight weeks before the election, rather than anything that might happen after.