As the prospect for the loss of the U.S.'s AAA credit rating approaches and congressional leaders agree on a pact to avert default, bonds and currencies are signaling increasing demand for the assets of the world's largest economy.

Treasury yields average 0.72 percentage point less than the rest of the world's sovereign debt markets, Bank of America Merrill Lynch indexes show. The difference has expanded from 0.15 percentage point in January. The dollar saw greater than average net inflows last week compared with the previous year, according to Bank of New York Mellon, the custodian for more than $20 trillion.

Investors from China to the U.K. are lending money to the U.S. government for a decade at the lowest rates of the year. For many of them, there are few alternatives outside the U.S., no matter what its credit rating. President Barack Obama said leaders of both parties in the U.S. House and Senate approved an agreement to raise the nation's debt ceiling and cut the federal deficit, in a televised speech yesterday in Washington.