The Vancouver-based company says it has invested $600 million (all figures in U.S. dollars) in the project expected to cost $1.2 billion when completed.
The plan is to create 29,000 kilometres of fibre-optic cable, linking South America to North America. It's expected to be complete in 2002, and the first section is scheduled to be done by March.
Critics say this kind of project is excessive for the marketplace, but Scott Lyons, 360's vice-president of submarine systems, disagrees.
"This is something that has been paying off because when you look at the major capacity sales in South America announced over the past few months, all the big ones are ours," he told the Globe and Mail.
Network investors include Montreal's Teleglobe Inc. and Calgary's Shaw Communications Inc. To date, 360 says it has sold $300 million worth of capacity on its South American network.
