Former U.S. Treasury Secretary Lawrence Summers and billionaire investor Redalio (Ray Dalio) said at the Qatar Economic Forum that the United States faces a period of overheating and inflation that could threaten the economic recovery, although the Federal Reserve has hinted that it will intervene before it happens.

Mr. Dalio, founder of Bridgewater, the world's largest hedge fund, said the Fed will not tighten policy further unless there are negative interest rates, and he is more concerned about the risk of inflation in financial assets.

"it is easier said than done when it comes to the fact that the Fed should tighten policy, and they should hit the brakes a little bit, but I think the market is very sensitive and the economy is also very sensitive because the duration of the relevant assets is quite long," it said.

Mr. Summers said the Fed had no basis for staying on hold on inflation.

Crude oil and gold prices were boosted by the fact that the dollar fell to an intraday low after the two men spoke.