The FBI served subpoenas on the White House and six of President Clinton's senior officials Friday night.
Special Prosecutor Robert Fiske is seeking testimony and documents related to his investigation into a failed Arkansas thrift with ties to the Clintons.
The subpoenas ask for information on contacts between White House staff and Treasury Department officials related to the federal inquiry, the White House said.
The disclosures of those meetings came this week, fueling Republican demands for a new inquiry into the Clintons' investment and put pressure on the president to act firmly to disavow the talks.
White House counsel Bernard Nussbaum was said to be planning to resign in the wake of questions about the contacts _ which included himself.
The Washington Post reported that Nussbaum told the president he would resign today. Clinton met with him late Friday in the Oval Office.
The multiple subpoenas underscored the extraordinary steps Fiske was taking in the early stages of his investigation into the failure of Madison Guaranty Savings and Loan Association.
As part of that inquiry, Fiske is trying to determine whether investors in a Arkansas real estate venture known as Whitewater _ including the Clintons _ benefited from questionable Madison transactions.
"The White House will comply fully and promptly with the subpoena," Press Secretary Dee Dee Myers said in a statement. Myers said that because the subpoenas concerned a pending investigation, the White House would have no further comment.
Subpoenas also were served on three officials at the Treasury Department who "intend to comply fully," said agency spokesman Howard Schloss.
Subpoenaed at the White House were Harold Ickes, deputy chief of staff; Bruce Lindsey, senior presidential adviser; Mark Gearan, the communications director; Nussbaum; Lisa Caputo, press secretary to Hillary Rodham Clinton; and Maggie Williams, Mrs. Clinton's chief of staff.
The flurry of legal activity at the White House came late on a day when Clinton had said he was determined to cooperate with investigators in hopes of putting the Whitewater issue to rest.
"I want this thing to be done fully, clearly and to be over with," he said at an afternoon news conference. "That is my only interest, and I intend to pursue it with great vigor."
A White House official sought to put the best face on the potential disruption of work among Clinton's key lieutenants.
"We'll go forward. It's like anything else in the world: You've got to work it in. It's not going to overwhelm the White House."
At Treasury, subpoenas went to Deputy Treasury Secretary Roger Altman, General Counsel Jean Hanson and Chief of Staff Joshua Steiner.
The White House subpoena directed the administration to preserve documents and records related to Whitewater, and it instructed the six staff members that they would be expected to testify before a grand jury.
At the same time, White House Deputy Counsel Joel Klein issued a notice barring the destruction of White House computer records.
He also issued notices to halt the removal of "burn bags" in the White House, stop the removal of trash containers and ordered the preservation of all computer records.
_ Information from the New York Times was used in this report.