Nov 30 (Reuters) - Gold prices were flat on Tuesday, as cautious investors assessed the extent to which the Omicron coronavirus variant could hurt the global economy.

FUNDAMENTALS

* Spot gold was unchanged at $1,785.13 per ounce by 0055 GMT. U.S. gold futures rose 0.2% to $1,784.30.

* The World Health Organization (WHO) said on Monday the Omicron coronavirus variant carried a very high risk of infection surges, while border closures by more countries cast a shadow over an economic recovery from the two-year pandemic.

* But a South African infectious disease expert said existing vaccines should be effective at preventing severe disease from the variant.

* U.S. Federal Reserve Chair Jerome Powell said on Monday he continues to expect inflation to recede over the next year as supply and demand come into better balance, but warned that the new strain of COVID-19 muddies the outlook, and prices could continue to rise for longer than earlier thought.

* Reduced stimulus and interest rate hikes tend to push government bond yields up, raising the opportunity cost of gold, which pays no interest.

* European Central Bank policymakers sought to reassure investors over the new coronavirus variant on Monday, arguing that the euro zone's economy had learned to cope with successive waves of the pandemic.

* Costs are rising at the fastest rate in over 20 years for firms in Britain's services sector, according to a business survey which shows why the Bank of England may soon raise interest rates.

* Platinum rose 0.4% to $966.58 an ounce, while palladium gained 0.4% to $1,801.27.

* Russia's Nornickel raised its 2021-2030 investment estimate to $35 billion, allowing the world's largest producer of palladium to upgrade its production infrastructure and raise its long-term outlook for PGM output.

* Spot silver was steady at $22.88 an ounce.

(Reporting by Nakul Iyer in Bengaluru; Editing by Rashmi Aich)