U.S. Republicans hammered President Barack Obama's handling of economy Tuesday after figures showed that the nation's public debt surpassed 16 trillion U.S. dollars.

According to the Treasury's figures, the total outstanding U.S. public debt hit 16 trillion dollars Tuesday, an increase of more than 5 trillion dollars compared with the level when Obama took office in 2009.

U.S. House Speaker John Boehner called the news "another sad reminder" of Obama's broken promise to cut government spending.

"Instead of working in a bipartisan way to fulfill his promise, the president went on a 'stimulus'-fueled spending binge that stuck every American man, woman and child with a 50,000 dollars share of this 16 trillion dollars national debt," Boehner said in a statement.

"This debt is a drain on our economy and a crushing burden on our kids and grandkids, and it's yet another indication that the president's policies have made things worse."

Boehner's criticism came just as the incumbent president prepares to accept his party's nomination for re-election.

Ryan Williams, a spokesman for the GOP presidential candidate Mitt Romney, also lamented the "enormous debt".

As of July, the combined budget deficit in the first 10 months of the 2012 fiscal year totaled 973.8 billion dollars, putting the country well on track for a deficit of over 1 trillion dollars for the fourth consecutive fiscal year.

In an updated U.S. budget and economic outlook report released last month, the U.S. Congressional Budget Office, a non-partisan budgetary agency, estimated that the budget deficit in 2012 fiscal year ending September will amount to 1.1 trillion U.S. dollars.