WASHINGTON, May 14 - The White House has been slow to establish an oversight board charged with ensuring that the government's campaign against terrorism does not erode privacy and civil rights, a bipartisan group of senators said in a letter released Friday.

Five months after the board was created, President Bush has yet to name any members or an executive director, and the $750,000 budget for the board proposed by the White House is far less than the budgets of other federal panels, the senators said.

"We urge the White House to take the steps necessary to allow the board to begin functioning effectively as soon as possible," the senators said in a letter to Andrew H. Card Jr., the White House chief of staff.

The letter was signed by Susan Collins, Republican of Maine, who leads the Committee on Homeland Security, and by three Democrats: Richard J. Durbin of Illinois, Joseph I. Lieberman of Connecticut and Patrick J. Leahy of Vermont.

The White House said in response to the senators' concerns that Mr. Bush remained committed to giving the board the staffing and resources it would need to monitor and protect civil liberties in the fight against terrorism.

Trent Duffy, a White House spokesman, declined to say when board members might be named.

"We're working to finalize a list of people," Mr. Duffy said, "and the hope is to move quickly on this." He rejected charges that the effort had gone too slowly, saying the president was "moving at the appropriate pace, and he wants to make sure the right people are on board."

The Sept. 11 commission, in its final report last summer, noted the absence of any centralized federal office to protect civil liberties in the campaign against terrorism, and it urged the creation of such an office. Congress moved on the idea last December as part of a broader restructuring of federal intelligence operations, creating the Privacy and Civil Liberties Oversight Board.

The move reflected a compromise that allowed the White House to retain control of the panel and its membership. Some House Democrats, calling the plan watered-down and ineffective, have proposed a more independent body with greater subpoena power, but that idea appears to have stalled in Congress.

In their letter to the White House, the four senators asked for a timetable and details on how the panel would be staffed and set up. The letter noted that the White House's proposed budget for the board fell well below the $13 million devoted to a civil rights office within the Department of Homeland Security, the $39 million for the Office of the United States Trade Representative and the $4 million for the Council of Economic Advisers.

Timothy H. Edgar, legislative counsel for the American Civil Liberties Union, said the White House's lack of action reflected a resistance to aggressive monitoring of civil liberties in the face of public concern about the government's use of data mining, toughened immigration controls, expanded surveillance powers and a host of other counterterrorism measures.

"With the centralization of power in the intelligence community," Mr. Edgar said in an interview, "you need to have some agency in government that's seriously looking at protecting civil liberties. Instead, you have a real lack of commitment from the White House, and they're not really doing much of anything."