NEW YORK (AFP) - Global markets surged Friday as President George W. Bush said he was ready to "risk" hundreds of billions of dollars to beat the financial crisis. With a top US senator estimating that one trillion dollars may be needed to soak up the debt that killed off Lehman Brothers and brought other Wall Street icons to their knees, central banks around the world again spent massively to steady the groggy markets. But Morgan Stanley still looked to be on the way to a forced marriage, and analysts differed over whether the turmoil had peaked. US stocks soared another 3.47 percent after a 3.5 percent gain Thursday when Bush announced that the US government would take drastic action to tackle the bad debts at the heart of the crisis. London's FTSE 100 index was up more than nine percent, Paris added 7.54 percent and Frankfurt put on more than five percent. Hong Kong shares closed up 9.6 percent and Tokyo closed up 3.76 percent. The dollar rose, oil went above 100 dollars a barrel and money came out of safe haven gold investments as Bush on Friday reaffirmed the US administration's determination to tackle the crisis while warning that success was not guaranteed. "This is a pivotal moment for America's economy," Bush said. "There will be ample opportunity to debate the origins of this problem. Now is the time to solve it." "These measures will require us to put a significant amount of taxpayer dollars on the line," he said. "This action does entail risk." But, he declared, "we expect that this money will eventually be paid back." Treasury Secretary Henry Paulson said Friday a rescue plan being worked on by the administration will cost "hundreds of billions" of dollars. Republican Senator Richard Shelby said the overall cost of the government intervention " which started with the takeovers of the Fannie Mae and Freddie Mac mortgage giants " could be one trillion dollars, including 500 billion for the new effort to clean up bad assets from bank balance sheets. "This needs to be big enough to make a real difference and get at the heart of the problem," Paulson told reporters ahead of talks in Congress on the massive rescue effort. He said legislative moves could start next week. The European, British and Japanese central banks again flooded markets with hundreds of billions of dollars to ensure that credit is available on strapped money markets. And in another step to instill market confidence, the US Securities and Exchange Commission and British regulators temporarily banned the short selling of shares in certain companies to check abuses. Short selling is borrowing shares in the hope they will fall, and selling for a profit, akin to self-fulfilling bets on a crash in times of extreme market distress. The action cheered all markets. On top of share gains, the dollar surged. In London, the euro fell to 1.4197 dollars from 1.4348 late Thursday. Gold, signalled a fall in the fear level, dropping to 855.5 dollars an ounce in Hong Kong from 875.5 dollars Thursday. Russian shares moved 12 percent higher after being suspended for three days in a row and Chinese share prices closed 9.46 percent higher " the fastest one-day rise in nearly seven years " after the government abolished a tax on buying shares to boost the market. But concerns remain. The Financial Times said Morgan Stanley was making "frantic attempts" to find a partner and was discussing selling a stake to China Investment Corp. which could end up with 49.0 percent from 9.9 percent now. The daily said the bank preferred to sell a stake to CIC to a merger with US bank Wachovia Corporation. However an unnamed CIC executive was quoted as saying in Beijing that taking a holding "could be very hard now as the purchase of a stake ... could be subject to the US government foreign investment review." Opinions varied Friday on whether the official actions to stem the vortex threatening the global economy are enough. "The creation of a huge government-sponsored vehicle to take on so-called toxic investments in the US, short selling restrictions ... are all having a positive effect," said CMC Markets dealer Matt Buckland. "The combined efforts are so great that there seems to be a coherent belief that this could actually be sufficient to draw a line under what has been a tumultuous 18 months for the markets." But John Kyriakopoulos, a strategist at National Australia Bank Capital, said the official action so far "merely stopped the bank funding crisis from getting even worse, rather than reversed it." Seiichi Suzuki, market analyst at Tokai Tokyo Securities, said: "The rally is a combination of a knee-jerk reaction to the reports of the new rescue plan and a mere tracking of movement on Wall Street." The latest vicious chapter of the 14-month-old US subprime crisis began at the weekend with the collapse of Lehman Brothers. That was followed by the 85-billion-dollar nationalisation of insurance titan AIG, a wave of other distress signals and the rescue of British bank HBOS Thursday. The crisis has also savaged other big Wall Street names such as Bear Stearns and Merrill Lynch.