Issa's office said in an early response that Holder's letter "only seems to indicate a willingness to offer a selective telling" of key events and that the chairman is still asking the Justice Department to explain "how it is prepared to alter its opposition to producing subpoenaed documents"

Earlier Thursday, Holder's allies on the committee mounted their own aggressive defense of the attorney general, circulating a memo to House Democrats that calls the Republican argument for contempt, laid out in a contempt citation last month, "irresponsible, unprecedented, and contrary to the rule of law."

For more than a year, Republicans have been leading an investigation into "Fast and Furious," which was launched in Arizona in late 2009 by Alcohol, Tobacco, Firearms and Explosives officials, with help from the U.S. attorney's office there. The operation's targets bought nearly 2,000 weapons over several months.