Companies in Peru's mining, steel and energy industries reinvested profits in expansion projects in the first quarter, boosting FDI to a 15 month high.
Traditionally, state-run banks have assumed a key role in infrastructure financing, but the private sector may participate more actively in this sector, according to speakers at the Brazil Investment Forum.
The two countries are set to create a fund of up to US$20bn mostly to finance infrastructure projects.
Petrobras refused to sell natural gas to the plant's operator, Eletrobras, over a multibillion-dollar debt related to unpaid fuel bills.
National oil company YPF, Pan American Energy and the local subsidiary of France's Total will account for 72% of the total.
Expansion of three pipeline networks will require approximately US$255mn of investment.