China stepped up its purchases of U.S. government debt late last year, increasing its holdings of Treasurys to an all-time record of $1.317 trillion in November, government data released this week revealed.

The statistics underscore how reliant the U.S. and Chinese economies are on one another even as political tensions occasionally emerge.

According to figures inadvertently released Wednesday evening on the U.S. Treasury Department website, China’s holdings of Treasurys increased by 0.9% in November to $1.317 trillion, up from $1.305 trillion in October. Year-over-year, China’s holdings rose 11.3% from $1.183 trillion.

The $1.317 trillion figure exceeds China’s previous record high in July 2011 of $1.315 trillion, according to the government data.

China’s appetite for government debt has been driven by its huge amount of foreign-exchange reserves, which surged to a record of $3.82 trillion at the end of 2013. The demand for Treasurys does not appear to have been seriously eroded by concerns about the U.S. fiscal situation.

In recent months, the U.S. has managed to slash the federal deficit thanks to higher tax revenue and payments from Fannie Mae and Freddie Mac. Earlier this week, the government revealed a budget surplus of $53 billion in December.

The additional purchases of Treasurys, which are believed to be among the most secure and liquid assets in the world, widen China’s lead in this category.

The next closest foreign holder of U.S. debt is Japan, which increased its holdings to $1.186 trillion from $1.174 trillion in October.

Following those Asian giants, the leading holder of Treasurys is a category called “Caribbean banking centers,” which includes the Bahamas, Bermuda, the British Virgin Islands and the offshore financial hub of the Cayman Islands. This group of countries held about $290.9 billion of Treasury securities in November, down from $291.9 billion in October.

Follow Matt Egan on Twitter @MattMEgan5