WASHINGTON -- China remained the top holder of U.S. Treasurys in January, but Japan threatened to take over the no. 1 position as a net buyer with another month of record holdings, the Treasury Department said Thursday.

Overall, foreigners were net buyers of long-term U.S. financial assets in January, according to the monthly Treasury International Capital report, known as TIC.

According to preliminary data, China's holdings rose nearly $8 billion to $1.160 trillion from $1.152 trillion in December.

Meanwhile, Japan continued to be a heavy net buyer of Treasurys, hitting a record level of $1.079 trillion in January. Japan remained the second-largest holder of Treasurys, lifting its holdings by $21 billion from December.

Among all foreign investors, net purchases of U.S. Treasury notes and bonds totaled $82.96 billion, compared with net selling of $14.90 billion in December. Private foreign investors bought a net in $47.39 billion Treasury notes and bonds.

Data for major foreign holders of Treasury securities will next month be revised to include holdings held by some countries on behalf of others, such as custodial accounts in the U.K. held on behalf of China.

The closely watched figure of net long-term securities transactions showed total buying of $101 billion in long-term U.S. securities in January, after purchases of $19.1 billion the month before.

More broadly, net purchases of long-term U.S. securities, including transactions that don't occur on the open market, totaled $84.4 billion following net buying of $2.8 billion the month before.

The monthly Treasury report highlights cross-border acquisitions of securities with maturities of more than one year including nonmarket transactions such as stock swaps and principal repayment on asset-backed securities.

The report's most comprehensive category, "monthly net TIC flows," includes non-market flows, short-term securities and changes in banks' dollar holdings. This measure of net foreign capital inflow was $18.8 billion, compared with an inflow of $95.2 billion in December. Financial market analysts consider the monthly data from the Treasury Department to be a significant but imprecise gauge of how easily the U.S. can finance its trade deficit.

U.S. data released last week showed the trade gap widened in January to its highest level in more than three years as exports to China and the debt-beleaguered euro zone plunged.

The TIC's data can be found on the Treasury's Web site at: http://www.treas.gov/tic.

-By Ian Talley and Tom Barkley, Dow Jones Newswires; 202-862-9285; ian.talley@dowjones.com

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