The dollar was weighed by news that the U.S. government may have to step in to salvage troubled mortgage lenders Fannie Mae and Freddie Mac with state ownership.
After doubts emerged this week about the capitalisation needs of the two government-sponsored bodies, the news that the government may intervene to return the two companies to public ownership made markets nervous.
Debt of Fannie Mae and Freddie Mac soared in their best one-day gain in history on Friday amid speculation that a government takeover of the housing giants would make the bonds more like ultra-safe U.S. Treasuries.
The prospects, sparked by deep consternation over the ability of the companies to survive on their own and a New York Times report saying the government is mulling a takeover, caused investors to flee the companies' stock, which some analysts said could be left worthless.
Investors were selling shares of the congressionally chartered companies and buying their debt, which if assumed by the government would be seen as safe as Treasury bonds, said Michael Kastner, head of fixed-income at Sterling Stamos Capital Management in New York.