Perdaman Chemicals and Fertilisers has signed a deal with WestNet to provide rail access for the company's Collie Urea project.

WestNet Rail chief executive Paul Larsen described the heads of agreement as a milestone for the project and a win for both companies.

Perdaman is developing a US$2.5 billion fertiliser manufacturing plant at Collie targeting 2 million tonnes of urea per annum to be exported through the port of Bunbury, utilising WestNet's rail network.

Perdaman chairman and managing director Vikas Rambal said the heads of agreement provided the framework for increased benefits for both parties with WestNet extending the use of the rail network and increasing track access revenue and Perdaman securing rail access which was vital to the project's success.