Stocks in the United States slid to 12-year lows on Monday after a record loss of $US61.7 billion loss by AIG.
AIG will receive an extra $US30 billion in assistance from the US government. It previously received $US150 billion last year.
British bank HSBC also announced it was seeking a huge capital injection to survive the economic crisis.
HSBC revealed on Monday that it needs nearly $US18 billion in new capital to withstand the financial crisis and announced 6100 job cuts.
The bank reported a fall of 70% in annual net profit last year and said it hoped to raise STG12.5 billion in a record rights issue.
The Dow Jones industrial average slid 299.64 points, or 4.24%, to end unofficially at 6,763.29.
Standard & Poor's 500 Index fell 34.27 points, or 4.66% , to finish unofficially at 700.82. The Nasdaq Composite Index lost 54.99 points, or 3.99%, to close unofficially at 1,322.85.