The fund has already invested around 8 billion euros ($8.4 billion) in Spain, including a 14.5% stake in power utility Naturgy, its flagship investment in the country.
"Our teams analyse all the infrastructure assets in the world in search of investment opportunities, and Spain will receive investments from IFM," Chief Executive David Neal told reporters.
IFM could channel its expansion into businesses like biogas through its stake in Naturgy, while it could go on its own or with different partners into other sectors, Jaime Siles, who represents the fund on Naturgy's board, said.
Siles mentioned data centres and mobile phone masts in the telecom industry, as well as biogas and renewables as businesses in which the company sees growth opportunities.
"We believe Spain has a big potential" in biogas, he said.
Neal, as well as IFM's global and regional infrastructure chiefs, Kyle Mangini and Deepa Bharadwaj, travelled to Madrid to meet major international investors.
The event comes at a sensitive time for Naturgy, following some tensions over the potential appointment of a chief executive and debates over a significant overhaul plan.
IFM confirmed its long-term interest in Naturgy and support for the management.
"We are comfortable with our position today," Mangini said.
"We are long-term investors, and we think in terms of decades, not years," he said.
($1 = 0.9498 euros)
(Reporting by Pietro Lombardi Editing by Inti Landauro and Mark Potter)
By Pietro Lombardi