America's financial regulatory system must be overhauled to strengthen oversight of banks, mutual funds and large financial institutions whose collapse would put the entire economy in peril, Federal Reserve Chairman Ben Bernanke said Tuesday. “We must have a strategy that regulates the financial system as a whole, in a holistic way, not just its individual components,” Bernanke said in a speech to the Council on Foreign Relations. The Fed chief's remarks come as the Obama administration and Congress are starting to crafting their overhaul strategies. For the administration, critical work on that front will be carried out among global finance officials this weekend in London. That will help set the stage for a meeting of leaders from the world's 20 major economic powers in April. Revamping the US financial rule book - a patchwork that dates to the Civil War - is a complex task. Congress, the administration and the Fed are involved because they want to strengthen the system to prevent a repeat of the financial crisis - the worst since the 1930s- that has plunged the US and many other countries' economies into recession. Bernanke said the US recession could end this year only if the government is successful in getting financial markets to operate more normally again. The recession, now in its second year and already the longest in a quarter-century, has turned out to be more severe than the Fed had anticipated, he acknowledged in fielding questions after his speech.