NEW YORK, Nov 30 (Reuters) - Global stock benchmarks and oil prices fell sharply on Tuesday after drugmaker Moderna warned that existing vaccines are unlikely to be as effective against the new coronavirus variant, spurring investors to pile into safe-haven assets such as government bonds and the yen. "There is no world, I think, where (the effectiveness) is the same level," Moderna"s (MRNA.O) chief executive, Stephane Bancel, told the Financial Times in an interview, comparing the effectiveness against the new Omicron variant to prior variants. "I think it"s going to be a material drop. I just don"t know how much because we need to wait for the data. But all the scientists I"ve talked to ... are like "this is not going to be good,"" Bancel said. read more Bancel said earlier on CNBC that there should be more clarity on the efficacy of COVID-19 vaccines against the Omicron variant in about two weeks, but it could take months to begin shipping a reworked vaccine designed for it. "It"s not good news, and it"s coming from someone who should know," said Commonwealth Bank of Australia currency strategist Joe Capurso. "Markets have reacted in exactly the way you"d expect them to." Losses accelerated after Federal Reserve Chairman Jerome Powell told Congress that high inflation will persist until the middle of next year, leaving the central bank "likely" to discuss speeding up the tapering of the asset-buying program it introduced last year to support the economy during the pandemic. read more A man looks at stock market monitors in Taipei January 22, 2008. REUTERS/Nicky Loh Traders work on the floor of the New York Stock Exchange (NYSE) in New York City, U.S., November 29, 2021. REUTERS/Brendan McDermid The German share price index DAX graph is pictured at the stock exchange in Frankfurt, Germany, November 29, 2021. REUTERS/Staff 1/3 Traders work on the floor of the New York Stock Exchange (NYSE) in New York City, U.S., November 29, 2021. REUTERS/Brendan McDermid "We"ve long maintained that the Fed is the ultimate owner of the "transitory" characterization and the chair"s decision to move beyond that is a decidedly hawkish step," said Ian Lyngen, head of U.S. rates strategy at BMO Capital Markets. MSCI"s gauge of stocks across the globe (.MIWD00000PUS) shed 1.39% following broad declines in Europe and Asia. Concerns that the new variant would lead to more travel restrictions continued to hammer European travel and leisure stocks, which posted their biggest monthly fall since the initial COVID-19 lockdowns in March 2020. In the United States, the Dow Jones Industrial Average (.DJI) fell 652.22 points, or 1.86%, to 34,483.72, the S&P 500 (.SPX) lost 88.26 points, or 1.90%, to 4,567.01, and the Nasdaq Composite (.IXIC) dropped 245.14 points, or 1.55%, to 15,537.69. Benchmark 10-year notes last rose 26/32 in price to yield 1.4426%, from 1.529% late on Monday. Omicron worries sent the yield on 10-year German Bunds - regarded as one of the safest assets in the world - to its lowest level in just over a week at -0.345% . The Japanese yen - traditionally viewed as a safe harbor due to its role as a funding currency - was near its highest level of the month. U.S. crude fell 4.52% to $66.79 per barrel and Brent was at $70.57, down 3.91% on the day