Ranking committee member Sen. James Inhofe, R-Okla., and 25 other Republican senators wrote to Levin, D-Mich., Wednesday demanding that Hagel provide the committee with more financial disclosure information on speeches he has made since leaving the U.S. Senate in 2009.
"This letter appears to insist upon financial disclosure requirements that far exceed the standard practices of the Armed Services Committee and go far beyond the financial disclosure required of previous Secretaries of Defense," Levin told Inhofe in a letter Friday.
Levin said Hagel, R-Neb., has complied with the committee's "well-defined set of financial disclosure and ethics requirements which apply to all nominees for civilian positions in the Department of Defense."
The committee had been expected to vote Thursday on President Barack Obama's nomination of Hagel to succeed Leon Panetta as defense secretary. Action was put off after Republicans demanded more financial disclosure, with some members saying they have questions about paid speeches Hagel has made and demanding more financial documentation for organizations with which he is affiliated.
Levin intends to have a committee vote on the Hagel nomination as soon as possible, his office said in a posting on his website Friday.
Inhofe on Wednesday said, "I will do what I can to see that [Hagel's nomination] fails."