Household debt grew at its fastest pace since early 2008 in the fourth quarter last year, a possible sign that the painful process of paring back borrowing in the aftermath of the financial crisis may have run its course.

Federal Reserve data released on Thursday also showed that the net worth of American households grew solidly during the fourth quarter of 2012, rising $1.1 trillion to $66.0 trillion, another hopeful sign for future U.S. consumer spending.

Household debt rose at a 2.5 percent annual rate in the fourth quarter, according to the Fed's quarterly Flow of Funds report. It was the steepest gain since the first quarter of 2008 and only the third quarter since then in which debt levels rose.

(Reporting By Alister Bull; Editing by Chizu Nomiyama)