May 18, 2004 — (Washington)The United States government has decided to halt monthly $335,000 payments to the Iraqi National Congress, the group headed by Ahmad Chalabi, an official with the group said on Monday.

Mr. Chalabi, a longtime exile leader and now a member of the Iraqi Governing Council, played a crucial role in persuading the administration that Saddam Hussein had to be removed from power. But he has since become a lightning rod for critics of the Bush administration, who say the United States relied on him too heavily for prewar intelligence that has since proved faulty.

Mr. Chalabi's group has received at least $27 million in United States financing in the past four years, the Iraqi National Congress official said. This includes $335,000 a month as part of a classified program through the Defense Intelligence Agency, since the summer of 2002, to help gather intelligence in Iraq. The official said his group had been told that financing will cease June 30, when occupation authorities are scheduled to turn over sovereignty to Iraqis.

Internal reviews by the United States government have found that much of the information provided as part of the classified program before American forces invaded Iraq last year was useless, misleading or even fabricated.

A Pentagon official said Monday night said he was not able immediately to confirm the status of the Pentagon's relationship with Mr. Chalabi's group. On April 27, Secretary of Defense Donald H. Rumsfeld, asked at a news briefing about whether the payments to Mr. Chalabi's group were going to end, said, "To my knowledge, that's not been determined."

The official of Mr. Chalabi's group said the classified program had originally been scheduled to end Sept. 30, 2003, but was extended twice — to Dec. 31, 2003, and then again, to June 30, 2004. The official said he did not know why the government decided not to extend the program again.

In recent months, Mr. Chalabi, once viewed as a potential leader of postwar Iraq, has been at odds with the Bush administration on a series of policy questions. He has criticized Lakhdar Brahimi, the United Nations official who is organizing an Iraqi government to take control of the country on July 1 and whose efforts have been embraced by the White House. He has also been at the center of a battle between the Governing Council and American occupation authorities over who should investigate corruption allegations in the United Nations oil-for-food program for Iraq.

The official of the Iraqi National Congress defended the group's intelligence-gathering, saying its role providing weapons intelligence had been overblown and that it had helped capture 1,500 insurgents, mostly loyalists of Saddam Hussein.

Michael Rubin, who spent eight months in Iraq as an adviser to the Coalition Provisional Authority, the occupation administration, and is now a resident scholar at the American Enterprise Institute, a conservative research center in Washington, said: "The truth of the matter is that the I.N.C.-provided information rolled up a lot of insurgent cells that were targeting American soldiers. It stopped bombings and terrorist attacks that were aimed at U.S. troops. That program saved a lot of lives."

But Mr. Chalabi's critics characterize him as a political opportunist.

On Sunday, Senator Joseph R. Biden Jr., the ranking Democrat on the Foreign Relations Committee, described Mr. Chalabi as a "darling of the vice president and of some of the civilians in the Defense Department," adding that Mr. Chalabi is "a problem" and "not part of the solution."

"There seems to be an unwillingness to break from him," Mr. Biden said on NBC's "Meet the Press."