Speaking at a conference in Taipei, Merrill Lynch Vice Chairman Richard T. McCormack also said he expected commodity prices to fall as demand slows.

"The challenge now for global leaders is to make sure the markets correct as orderly as possible," McCormack said. "Everybody is doing what they can. The problem is no one knows for sure (when the crisis will be over)."

McCormack's comments come after stocks around the globe plunged on Monday, on doubts that a scattered European response to the financial crisis and a $700 billion US bank bailout could prevent a deeper slump in the global economy.

With few signs world markets would improve soon, one thing governments around the world can do is to make financial systems safer, McCormack said.

"They should take more effective supervisory measures," he said.

In the longer term, markets would pick up, he added.

"Warren Buffett has poured billions of dollars in some distressed assets," he said, adding that he has said before investors should be greedy when everyone else is afraid.