"The minister appeared to have no knowledge of alarming developments.
"While the minister reiterates the same phrase, that there are no plans to close any rail lines in Northland, National has already shut down the Dargaville line. We are suspicious that the Government is simply letting rail fail."
He called for an upgrade of the line in Northland and the rail link to Marsden Point to go ahead to support long term development of NorthPort, with efficient and well-maintained rail infrastructure one of the solutions to building Northland's economy.
"This would be the first country in the world to abandon rail infrastructure," Mr Peters said.
Mr Bridges said KiwiRail, which runs the rail network, considers that the Northland line's economics are challenging.
"This is because almost 99 per cent of Northland's freight and 100 per cent of its passenger travel is carried on the roads but there are no current plans to shut the line," he said.
"The Government is investing significantly in KiwiRail - it has been allocated $400 million in funding over the next two years, and some $3 billion has been spent on rail infrastructure."
Mr Peters has his Waitemata Harbour Protection Bill in the Parliamentary ballot.
If selected and passed it would freeze the Ports of Auckland's growth to its physical footprint as of March 27, 2015.
Labour will support the bill to at least select committee stage.