The dollar rose for a second straight session Friday as risk tolerance declined, with investors cutting exposure to assets and currencies perceived as higher risk ahead of a holiday-shortened week in the United States.

The dollar and yen rose Thursday as a pullback in risk appetite amid declines in equity and commodity markets revived safe-haven demand for the U.S. and Japanese currencies.

The dollar fell against most major currencies Wednesday as dealers took profits on the currency's biggest rise in three weeks, with fresh data doing little to alter the view that U.S. interest rates will remain at record lows well into 2010.

European Central Bank President Jean-Claude Trichet on Tuesday backed comments by U.S. Federal Chairman Ben Bernanke about the importance of a strong dollar and said a sound U.S. currency was in the interests of the whole world.

The dollar rebounded Tuesday from a 15-month low after Federal Reserve Chairman Ben Bernanke's rare comments on the currency spurred traders to trim long-term bets against the greenback.

The dollar fell broadly Monday though it rose from session lows after Federal Reserve Chairman Ben Bernanke said the U.S. central bank is attentive to changes in the dollar.

The dollar fell across the board Friday after unexpectedly weak trade deficit and consumer sentiment figures stoked worries about the outlook for a U.S. economic recovery.

The dollar rose broadly Thursday as several policymakers around the world warned the economic recovery was fragile, prompting investors to take profits on gains in higher-yielding currencies and assets.

The dollar rallied from a 15-month low against major currencies Wednesday in a technical rebound after selling pressure failed to push the U.S. currency through key levels.

The dollar firmed Tuesday from the 15-month low touched in the prior session as investors saw Monday's fall as too far, too fast.

The dollar fell to a 15-month low against a basket of major currencies Monday and the euro rose above $1.50 after the Group of 20 pledged to keep emergency stimulus spending in place until a global recovery is assured.

The dollar is likely to trade higher in the week ahead, with Friday's worse-than-expected U.S. non-farm payrolls data for October seen as the driving force for currency markets at least until mid week.

The dollar and yen rose Friday after a report showed the U.S. unemployment rate spiked and the economy lost more jobs than expected, stoking concerns about the U.S. economy and restoring safe-haven demand for both currencies.

The European Central Bank kept its main refinancing rate unchanged at a record low of 1.0 percent on Thursday, as expected by economists.

Investors are braced for signs on Thursday that the European Central Bank will soon start weaning banks off cheap and abundant liquidity given that expiry dates are approaching for the central bank's crisis measures.