WASHINGTON (AP) _ A third former Clinton administration official refused Thursday to give Congress documents subpoenaed for investigations of Democratic fund-raising _ claiming a Fifth Amendment privilege against self-incrimination.

The refusal by former White House aide Mark Middleton to turn over documents came as the head of the Senate probe warned that a stalemate over his budget must be resolved quickly or there will be no money for the investigation.

Sen. Fred Thompson, R-Tenn., has proposed a $6.5 million budget for the investigation by the Governmental Affairs Committee that he chairs. Democrats insist that $1.8 million is enough and have threatened a filibuster.

``The investigative budget expires tomorrow,'' Thompson said. ``We need to resolve this next week. We are going to run out of money.''

Committee Democrats met Thursday night but did not change their position that $1.8 million is enough, according to Sen. John Glenn, the ranking minority member of the panel.

Glenn said Republicans got themselves in a bind by placing ``the cart before the horse. We should have had the resources before we started issuing subpoenas.''

Senate Majority Leader Trent Lott, R-Miss., filed a resolution Thursday night to finance the committee at $5.7 million, indicating he wants to bring the issue to a head with a vote on the Senate floor next week. Under the resolution, another $800,000 would come out of the FBI's budget for use of 25 agents who would be temporarily assigned to the Senate investigation.

Senate Minority Leader Tom Daschle, D-S.D., said Democrats would try to block such a vote until Republicans set a date to vote on campaign finance legislation.

The $4.5 million budget that Thompson's panel has received for the fiscal year beginning Saturday does not include extra money for the campaign-finance investigation.

Besides refusing document subpoenas, Middleton said in a statement that he would also invoke his Fifth Amendment privilege to resist demands to testify in any congressional hearings held by House and Senate committees.

Middleton said that the allegation he had ``improperly solicited a $15 million campaign contribution in Taiwan has proved to be false and my sole accuser has recanted his own accusation.''

``Unfortunately, the truth has made so little different to the tone or substance of public discourse that I am convinced that for now, I should postpone further opportunities to speak publicly about these matters,'' Middleton said.

Middleton, however, said he would cooperate with the Justice Department's criminal investigation.

Middleton is the third former Clinton administration official to claim a Fifth Amendment privilege in refusing to turn over documents to congressional investigators.

Former Associate Attorney General Webster Hubbell and ex-Commerce Department official John Huang have also refused to give documents to a House committee. Huang, who became a top Democratic National Committee fund-raiser, has turned over some documents.

Legal experts say courts generally do not recognize a Fifth Amendment privilege against document production. But Middleton's refusal signals he would seek a grant of immunity from Congress that would prevent prosecutors from using whatever he says at hearings.

Middleton, who worked as a deputy to senior presidential advisor Mack McLarty, left President Clinton's staff in 1995 to become an international business consultant. He returned to the White House 65 times and frequently used the private restaurant, where, presidential aides say, he may have entertained private clients.

In other developments:

_Attorney General Janet Reno said the Justice Department is expanding its task force investigating allegations of Democratic campaign fund-raising abuses. But Reno said investigators had not found evidence to warrant seeking appointment of an independent counsel.

_FBI agents assigned to the Justice task force have begun investigating whether the People's Republic of China may have attempted to influence members of Congress through illegal campaign contributions, The Washington Post reported Friday. An informal inquiry was begun several months ago before the task force was created after wire intercepts indicated Chinese officials were trying to win influence among some members of Congress. The Post quoted government officials as saying the FBI has not identified any lawmaker who may have received such a contribution.

_White House spokesman Mike McCurry said President Clinton had not hosted any big-money contributors as overnight guests in the executive mansion in recent weeks. That didn't mean Clinton had renounced the practice, he said. ``It just means that there haven't been any here recently.''

_Sen. Christopher Dodd, D-Conn., and a former co-chairman of the DNC, urged the White House in 1995 to continue rewarding big Democratic donors with special access to Clinton and Vice President Al Gore, according to a July 11, 1995 memo to Clinton from his then deputy chief of staff, Harold Ickes. The memo, part of a package of documents released Tuesday, noted that Donald Fowler, who shared the chairmanship of the Democratic Party with Dodd, wanted to halt the practice.

_ABC News reported that Clinton raised $1 million at a dinner last September in Illinois where Brady Williamson, Clinton's appointee to chair the National Bankruptcy Review Commission, was a featured guest. The report said most of the contributions came from bankruptcy lawyers and bankers. ABC also reported that the Justice Department is considering filing obstruction of justice charges against Pauline Kanchanalka, a Thai businesswoman whose $253,000 in contributions to the DNC were returned after she acknowledged that she was not the source of the money.