Foreign demand for U.S. Treasury securities rose to a record level in June, as China, the largest buyer of Treasury debt, increased its holdings.

The Treasury Department says total foreign holdings rose 0.7 percent in June to a record $5.29 trillion. It marked the sixth straight monthly gain.

Demand for U.S. debt is rising in part because investors are worried about Europe's debt crisis and its impact on the global economy. U.S. government debt is considered one of the world's safest investments.

China increased its holdings by $300 million, or 0.03 percent, to $1.16 trillion. It had reduced its holdings by $400 million in May. Japan, the second-largest buyer of Treasury debt, increased its holdings by 0.9 percent in June to $1.12 trillion.