Calling the administration's refusal to turn over documents ''frustrating and extremely difficult to understand,'' Comptroller General David M. Walker said today that it was likely he would need to sue the White House to force disclosure of information about President Bush's energy strategy.

Mr. Walker, who heads the General Accounting Office, an investigative arm of Congress, said he would make a final decision on whether to take legal action against the Bush administration this month. The accounting office has never before sued another government department for failing to cooperate with an inquiry.

''I don't think that it's a good idea for one part of government to sue another part,'' Mr. Walker said in an interview today. ''But we are on the right side of this, and if we have to go to court, we will go.''

The G.A.O. has been investigating how Vice President Dick Cheney and his top aides compiled the Bush administration's energy plan and has demanded the names of outsiders, including business executives and lobbyists, who met with administration officials to express their views.