Gold climbed higher on Tuesday as investors sought safe havens again after Moderna's CEO warned COVID-19 vaccines were likely to be less effective against the Omicron variant, putting bullion on course for a second straight monthly gain. Spot gold rose 0.4% to $1,792.23 per ounce by 1255 GMT, while U.S. gold futures advanced 0.5% to $1,794.70. The Moderna chief's comments rattled financial markets, leading to a slide in European equities. The U.S. dollar index (.DXY) also fell 0.6%, helping gold's advance by making it a cheaper bet for overseas buyers, while U.S. benchmark 10-year Treasury yields hit their lowest in three weeks."The risk-off sentiment is re-gaining momentum, as investors and portfolio managers are still evaluating the potential risk of the Omicron coronavirus variant," said Carlo Alberto De Casa, external analyst at Kinesis Money. "Investors are betting that this could slow-down the Fed's tapering. Therefore the U.S. dollar is losing ground and the scenario is supportive for gold," De Casa added. Gold tends to benefit from stimulus measures as it raises the prospect of inflation which bullion is used to hedge against, but interest rate hikes raise the opportunity cost of holding gold. read more Fed Chairman Jerome warned on Monday that the new COVID-19 strain muddied the central bank's inflation outlook and prices could continue to rise for longer than thought. read more Gold could still march towards $1,900 by end-year due to the renewed economic concerns, Commerzbank analyst Daniel Briesemann said, adding silver could track gold's gains. Elsewhere, spot silver fell 0.2% to $22.85 per ounce, platinum was down 1.4% to $949.99, and palladium shed 2% to $1,758.96. Reporting by Arundhati Sarkar in Bengaluru; Editing by Edmund Blair and Louise Heavens Our Standards: The Thomson Reuters Trust Principles.