NEW YORK (Bloomberg) — Central banks flush with record reserves are increasingly snubbing dollars in favor of euros and yen, further pressuring the greenback after its biggest two-quarter rout in almost two decades.

Policy makers boosted foreign currency holdings by $413 billion last quarter, the most since at least 2003, to $7.3 trillion, according to data compiled by Bloomberg. Nations reporting currency breakdowns put 63 percent of the new cash into euros and yen in April, May and June, the latest Barclays Capital data show. That's the highest percentage in any quarter with more than an $80 billion increase.

World leaders are acting on threats to dump the dollar while the Obama administration shows a willingness to tolerate a weaker currency in an effort to boost exports and the economy as long as it doesn't drive away the nation's creditors. The diversification signals that the currency won't rebound anytime soon after losing 10.3 percent on a trade-weighted basis the past six months, the biggest drop since 1991.

"Global central banks are getting more serious about diversification, whereas in the past they used to just talk about it," said Steven Englander, a former Federal Reserve researcher who is now the chief US currency strategist at Barclays in New York. "It looks like they are really backing away from the dollar."

The dollar's 37 percent share of new reserves fell from about a 63 percent average since 1999. Englander concluded in a report that the trend "accelerated" in the third quarter. He said in an interview that "for the next couple of months, the forces are still in place" for continued diversification.

America's currency has been under siege as the Treasury sells a record amount of debt to finance a budget deficit that totalled $1.4 trillion in fiscal 2009 ended September 30.

Intercontinental Exchange Inc.'s Dollar Index, which tracks the currency's performance against the euro, yen, pound, Canadian dollar, Swiss franc and Swedish krona, fell to 75.77 last week, the lowest level since August 2008 and down from the high this year of 89.624 on March 4. The index, at 76.104 yesterday, is within six points of its record low reached in March 2008.

Foreign companies and officials are starting to say their economies are getting hurt because of the dollar's weakness.

Yukitoshi Funo, executive vice president of Toyota City, Japan-based Toyota Motor Corp., the nation's biggest automaker, called the yen's strength "painful". Fabrice Bregier, chief operating officer of Toulouse, France-based Airbus SAS, the world's largest commercial planemaker, said on October 8 the euro's 11 percent rise since April was "challenging".

Developing countries have likely sold about $30 billion for euros, yen and other currencies each month since March, according to strategists at Bank of America-Merrill Lynch.

That helped reduce the dollar's weight at central banks that report currency holdings to 62.8 percent as of June 30, the lowest on record, the latest International Monetary Fund data show. The quarter's 2.2 percentage point decline was the biggest since falling 2.5 percentage points to 69.1 percent in the period ended June 30, 2002.