17th August 2009 - Meltdown 101: Foreign investments in US debt (WP)

In a listing of those countries, or country groups, which have lent the most money to the United States, OPEC countries are ranked fourth: "$191 billion: The amount collectively held by Saudi Arabia, Venezuela and 13 other oil exporters". China and Japan head the list. The United States is in debt to each of these countries in sums exceeding US dollars 700 billion.