Herb Allison, the head of the government's $700 billion financial bailout program, announced on Wednesday that he would resign.

Allison said in a letter to his colleagues in the Treasury Department's Office of Financial Stability that they had accomplished a great deal.

He said that the bailout fund, known as the Troubled Asset Relief Program, had proven to be remarkably successful in achieving its goal of stabilizing the nation's financial system and laying the groundwork for an economic recovery.

Allison said he was stepping down to return to Connecticut. He will be succeeded on an interim basis by Tim Massad, who is currently the chief counsel and chief reporting officer for the bailout program.

Massad, 54, will become acting assistant Treasury secretary for financial stability, effective on Sept. 30. Before joining government, Massad had been a partner for 17 years at the New York City law firm of Cravath, Swaine & Moore.

The $700 billion bailout program was created by Congress in October 2008 at the height of the financial crisis. The TARP program cannot commit money to new programs as of Oct. 3, although it will continue to support existing programs.

Treasury Secretary Timothy Geithner, in a statement, said that he wanted to "praise and celebrate" the work done by the people in the TARP program.

"I want to first recognize that while we have succeeded in putting out the financial fires that caused this deep economic crisis, we have not yet repaired all the damage," Geithner said in remarks to Treasury employees of the TARP program.

The TARP program, which began under President George W. Bush, became a frequent target of Republican attacks and the general public. Many people questioned the government rescue of big banks at a time when unemployment was surging and thousands of Americans were losing their homes to foreclosure.