The MP said he had seen a memorandum of understanding (MoU), or at least statement of intent, between Northland Regional Council (NRC) and China Rail, a document he said clearly states China's desire to build transport links between Whangarei and Northport.
Mr Peters said such an outcome would be "extraordinary, dangerous and a recipe for disaster".
The New Zealand Transport Agency announced three weeks ago that it would upgrade the 22km highway stretch. A spokesperson was unavailable at edition time to answer questions about the rumoured China Rail funding offer.
NRC chief executive Malcolm Nicolson denied claims there was already an MoU with China Rail, although he admitted one was in the pipeline.
Other claims about any NRC involvement in the road and rail link job were "outrageous", he said.
"This council clearly has no ability to decide on roading contracts and we're not in the business of building railway lines."
At its last meeting the council went into confidential mode to revisit discussions the previous council started about a possible understanding with China Rail, Mr Nicolson said.
"We have looked at it in principle before and what was discussed last week was the kind of language and scope the document might contain."
An MoU would only be a "high-level" paper outlining the council's role and the kind of relationship it could have with China Rail, Mr Nicolson said.
The NRC has designated the land for the rail link.
Also being talked about in the media and some political circles is a claim China Rail is proposing that 1000 Chinese people working on the multi-million SH1 job live on a cruise ship berthed off Port Marsden - an idea that has piqued Mr Peters.
"If we think we're getting a soft job from the Chinese to build a port and rail link, which they want, using cheap Chinese and steel, built by thousands of Chinese workers living in ships parked offshore, while New Zealanders and especially Northland people are crying out for jobs . . . Well, it's not going to happen," he said.
On one hand Northland desperately needed infrastructural, job and economical development; on the other hand, there needed to be home-based control of assets, jobs and adding value to resources, he said.
Mr Nicolson agreed the NRC could also be seen to be in a dilemma; charged with both facilitating infrastructural and economic growth through its legislation and its Northland Inc arm, but making sure benefits such as job creation went to Northland.
Mr Peters said that despite any agreements the NRC might make with China, or China Rail with local business, no deal could go ahead without central government approval.
But among questions he said had not yet been answered were how that road would be paid for and how it would be finished within three to five years of its 2019 start time.