Logistics giant Aurizon has launched legal action that could put the brakes on a deal that would deliver a $2 billion regional railway operation to Macquarie Group fund and its Dutch pension fund partner.

Aurizon on Tuesday lodged a claim in the NSW Supreme Court alleging that a move by Genesee & Wyoming's (G&W) incoming owner, Brookfield Infrastructure Partners, to sell its Australian operations breaches contracual obligations from an earlier deal.

Brookfield has proposed selling its 51 per cent stake in G&W to Macquarie Infrastucture and Real Assets (MIRA) and Dutch pension fund manager PGGM.

MIRA and PGGM already hold 49 per cent of G&W's local business under a deal struck in 2016.