He then expressed concern about an email that all MPs had recently received about their case and said the threatening tone in the email would be guaranteed to put an end to his approach.
"If this next two and a half weeks is so critically important to have that tone, then go ahead and do it, no problem, and we will see what the consequence is.
"If another two and a half weeks doesn't matter to you, then for goodness' sake don't do any more ... weigh it up and see what you think."
Dr Reti said he would approach ministers again to see if the issue was still on the table, whether it was still moving forward or had slipped off.
"Whatever strategy you think the best, you should and must do," he told Alex Wright, "but I just want to give you a brief heads up for my piece of work in this."
Economic Development Minister Steven Joyce confirmed yesterday that the Puhoi to Warkworth part of the Puhoi to Wellsford Highway - dubbed the "holiday highway" by Labour - would begin next year and would take years to build, at a cost of $760 million.
Until this 2016 confirmation, the highway's start date had been put at somewhere between 2016 and 2018 and its finish date somewhere between 2022 and 2025.
National's byelection candidate, Mark Osborne, was accompanied by Transport Minister Simon Bridges on the campaign trail yesterday to visit major roading projects. Among them was the Maromaku slip, where repairs are being done on 70m of State Highway 1 hit by floods last July.
Meanwhile, New Zealand First leader Winston Peters had fun on the campaign trail yesterday, visiting a butcher shop in Kaitaia to point to the "pork specials".