Toroama made the statement just ahead of the Pacific Sustainable Infrastructure Conference in Brisbane, which Bougainville attended this week, Radio New Zealand Pacific reports.
He said the autonomous Papua New Guinea region has seen little progress in the 18 years since the first Bougainville government was elected in 2005, and he wants to change that.
The president says the agreement provides a framework to deliver key infrastructure in a short timeframe.
It would be for government buildings, schools, hospitals, airport, sea ports, bridges, roads, power, telecommunications, and other essential infrastructure.
Funding is yet to be obtained.
"The infrastructure agreement represents a momentous step for the ABG towards building a prosperous future for Bougainville through substantial advancements in critical infrastructure development," he said in a news release.
The companies involved include the Bougainville Public Private Partnership Ltd, which will be responsible for raising the funds and the project delivery.
PNG engineering and architecture company Kramer Ausenco also has a role, along with Bougainville Islands Group Ltd, which the Bougainville government says has agreed, in principle, to provide land for the projects.
Toroama said the Autonomous Bougainville Government would be working together in partnership with the companies "to deliver transformative benefits for the people of Bougainville".
The Pacific Infrastructure Conference involved political, business representatives from the Pacific Islands, Australia, New Zealand, the USA, Japan, France, and various international partners, including the Asian Development Bank, the World Bank, and United Nations Development Programme.
