"Whether you believe the science or not, investable markets are being created by governments, and these investable markets we think will grow significantly over the next 20 to 30 years," he said at the launch of a report on climate change investment.

The bank has attracted around 6 billion euros (US$8.55 billion) into climate change funds, which target firms with products that cut greenhouse gases or help people adapt to a warmer world, in sectors from agriculture to power and construction.

It is hoping to tap into a growing awareness of the cash to be made from cleaner technology -- once more a preserve of idealists than hardnosed investors.

"We believe the shift away from a carbon-based economy is a megatrend that will shape the asset management industry for many years," Kevin Parker, global head of asset management, said in a statement.

"We expect return opportunities in sectors like renewable energy, water, and agribusiness will justify dedicated strategies."

The fund is not seeking tiny start-ups or firms with radical environmental credentials. Companies must have a market capitalisation of at least 200 million euros and a minimum 20 percent free float to be considered.

Its top ten holdings include French utility Veolia Environnement, Spanish building and construction group Acciona and diversified US manufacturer United Technologies Corp.