By keeping interest rates at all-time low levels, the U.S. faces the potential for a second major financial crisis, cautioned David Einhorn, the hedge fund manager.

The crisis that required zero interest rates has passed, Einhorn told the British newspaper the Telegraph. By not hiking rates then it increases the chance that governments will over-borrow and fall into a debt trap.

The comments come as The Federal Reserve prepares to launch a second round of quantitative easing of up to $600-billion. Interest rates in the U.S., UK and Europe have remained at historic lows since the onset of the global recession in late 2008.

If interest rates ever do go up again, you have another crisis, he said.

Einhorn, the founder of Greenlight Capital, is famous for being among the first to publicly warn that Lehman Brothers was facing a financial collapse in 2008. He also became embroiled in a lengthy dispute with lender Allied Capital, which he accused of using misleading accounting practices.

According to the Telegraph, Greenlight’s largest since position is in gold, which is poised to record a tenth consecutive year of gains and recently touched another all-time high in price.