KiwiRail is taking expressions of interest in regard to the electrification of Auckland's rail network.
It has alerted prospective suppliers to the project and its deadline of 2013 and hopes to have a short-list compiled by July this year.
KiwiRail chief executive Jim Quinn says there are only a few companies worldwide that will be able to meet the project's requirements.
Mr Quinn says ideally, he would like to have a contract signed by early next year.
