Under the agreement, Hawsons will be entitled to draw down the funding at its discretion by issuing put options over four years.
Hawsons will also issue 71.5 million options to LDA, which, if exercised, would see the company receive a further $50 million.
Hawsons executive chairman Bryan Granzien said the investment was a major milestone.
"It is a strong signal to capital markets that we have a credible global funding option in place to assist the development of our world-class Hawsons iron project," he said.
Hawsons recently raised $36.5 million for the project's bankable feasibility study, which is expected to be completed by December 2022.
A 2017 prefeasibility study confirmed the project was capable of producing one of the world's highest grade iron ore concentrates at 70% iron.
Hawsons was the biggest mover on the ASX, up 42% to 22c, a 52-week high.