LONDON, Dec 7 (Reuters) - Waning Omicron variant worries and a timely booster shot of Chinese stimulus lifted world stock markets and oil on Tuesday, and left traders offloading safe-haven currencies and bonds again. Europe"s FTSEurofirst (.FTEU3) was on track for its first back-to-back run of plus 1% gains since February. Wall Street was poised to rally , while Asia had cheered record bounces by some of China"s beaten down tech giants. (9988.HK), (9888.HK). The risk-on mood also helped the dollar climb against currencies such as the Japanese yen, , which had lost 0.6% overnight, as the confidence-sensitive Australian dollar also found buyers. Safe-harbour German government bonds went the other way with yields - which move inverse to prices - up 2.5 basis points after falling to a three-month low on Monday. Britain"s prime minister warned Omicron looked the most contagious coronavirus variant yet, but reports in South Africa said cases there had only shown mild symptoms and top U.S. infectious disease official, Anthony Fauci, told CNN "it does not look like there"s a great degree of severity" so far. "Good news relating to the severity of Omicron should be taken with a pinch of salt. Faster transmission could offset the benefits of milder symptoms," researchers at ING said in a note. "More broadly, it is still early days, even if markets are starting to display Omicron fatigue." The gains also came after China"s central bank on Monday injected its second shot of stimulus since July by cutting the amount of cash that banks must hold in reserve. read more There was still uncertainty about its property sector as Evergrande teetered on the brink of default again read more but data showing much stronger import growth was "a positive sign on the strength of domestic demand," RBC analyst Adam Cole said. E-commerce giant Alibaba"s shares (9988.HK) bounced from its record low to soar 12.2%, while Tencent (0700.HK) and Meituan (3690.HK) added 3.6% and 5.8%, respectively. Shares in embattled developer Evergrande (3333.HK) also edged off a record low as markets waited to see if it had made an already-overdue $82.5 million bond payment or formally slumped into default. BIDEN-PUTIN Elsewhere, Australia"s S&P/ASX200 (.AXJO) rose nearly 1% as its central bank left interest rates at a super-loose 0.1% read more and Japan"s Nikkei (.N225) advanced 1.9% as the yen dipped back. "We have had the Fed hawkish turn and Omicron hitting the market with both barrels recently but this week we have seen some dribbles of better news on Omicron," Saxo Bank"s head of FX strategy John Hardy said. "The yen has snapped back lower and the commodity currencies have turned higher ... it"s just snap back for now though rather than a trend," he added, cautioning it was too early to make conclusions about Omicron. Also supporting the dollar in FX markets was the expectation the Federal Reserve will accelerate the tapering of its bond-buying programme when it meets next week in response to a tightening labour market. Oil prices jumped another 2% to $74.60 a barrel, adding to a near 5% rebound the day before as concerns about the impact of Omicron on global fuel demand eased. That provided no protection for Russia"s rouble, which fell 0.3% on worries a renewed conflict in Ukraine could see the United States and Europe slap heavy sanctions on Russia"s banking system and the Nord Stream 2 gas pipeline. read more U.S. President Joe Biden and Russian President Vladimir Putin will hold a video conference at around 1500 GMT. read more "God knows what the delta risk is on that meeting but the U.S. is waving around the threat of more serious sanctions," Saxo"s Hardy said, adding the "nuclear option" would be banning Russian banks from the international bank-to-bank payment system called SWIFT.