In a speech at a financial conference in Abu Dhabi on Tuesday, billionaire investor Ray Dalio, founder of hedge fund Bridgewater, said he would invest in "hard currencies" such as gold and bitcoin while avoiding debt assets as most major economies face rising debt problems. "I think the debt currency issue may be coming, and I want to avoid debt assets like bonds and debt and hold some hard currencies like gold and bitcoin," he said. Citing "unprecedented levels" of debt in all major countries, including the US, the veteran investor stressed that current levels were unsustainable. "It is not possible for these countries not to have a debt crisis in the next few years, which would lead to a significant depreciation in the value of their currencies," he said.