Treasury Secretary Henry Paulson said global financial markets remain severely strained, underscoring the need for quick action to implement the government's $700 billion rescue program.
Paulson said all the financial market turmoil has seriously affected the economy, but he said the administration is moving quickly to begin the largest government rescue effort in history.
He said even with this program to buy bad assets from financial institutions, some banks will fail.
He also called for patience saying "the turmoil will not end quickly and significant challenges remain ahead."
"Governments have and must continue to take individual and collective actions to provide much-needed liquidity, strengthen financial institutions through the provision of capital...and protect the savings of our citizens,'' he said in a statement.
Paulson, along with Treasury Under Secretary David McCormick, spoke ahead of Friday's Group of Seven gathering of finance ministers and central bankers from rich nations that is to focus heavily on the effort to calm markets.
Paulson recited the numerous measures that members of the G7—the United States, Britain, Canada, France, Germany, Italy and Japan—and others have taken to try to halt plunging stock prices and rebuild confidence, but said more was needed.
"We must also take care to ensure that our actions are closely coordinated and communicated so that the action of one country does not come at the expense of others or the stability of the system as a whole,'' Paulson said.
(Treasury Secretary Henry Paulson discusses today's coordinated global rate cut. Watch the accompanying video for more...)
The United States garners much of the blame for the global crisis, which originated in subprime mortgage markets for risky borrowers and has since tainted nearly all classes of lending and caused banks to hoard capital.
Paulson said he wants a special meeting the Group of 20, which includes key emerging-market countries that also are hard-hit by the financial crisis, after the G7 meeting.
—Reuters contributed to this story.