Chief United Nations weapons inspector Hans Blix said today that Iraq still has not shown "genuine acceptance" of demands that it disarm, and has failed to demonstrate active cooperation with inspection efforts.

In a much-anticipated report on the first 60 days of U.N. inspections of Iraq's chemical, biological and nuclear weapons programs, Blix told the Security Council the Iraqi government has "cooperated rather well" in providing access to inspection teams.

But "it is not enough to open doors," he said, adding that the level of cooperation by Baghdad required by U.N. resolutions continued to be often "withheld or given grudgingly."

Although he did not ask to be given more time, Blix underscored the value of continuing inspections.

In a more positive overall assessment, Mohamed ElBaradei, director general of the International Atomic Energy Agency, said the IAEA should be able "within the next few months to provide credible assurance that Iraq has no nuclear weapons program." Those few months, he said, "would be a valuable investment in peace, because they could help us avoid a war."

Far from resolving the bitter dispute that has left the United States deeply divided from most of the Security Council and some of its closest European allies, the presentations today seemed to harden positions on both sides. Only moments after the inspectors delivered their assessments, U.N. ambassadors lined up before the media outside the council chamber to issue statements that clearly had been prepared before Blix and ElBaradei uttered a word.

"Iraq is back to business as usual," repeating the "denial and deception" that characterized earlier U.N. inspections, said U.S. Ambassador John D. Negroponte. "The danger is that the council may return to business as usual as well" in failing to do anything about it.

Secretary of State Colin L. Powell emphasized the message in a Washington news conference, saying, "The issue is not how much more time the inspectors need to search in the dark. It is how much more time Iraq should be given to turn on the lights and to come clean" before disarmament by force becomes the only option. "The answer," Powell said, "is not much more time."

But representatives from France, Russia, China and Germany said the reports demonstrated that inspections are working and should be allowed to continue.

"The system we set up . . . is producing results," said France's U.N. ambassador, Jean-Marc de la Sabliere. "But we need now a more active cooperation from Iraq and we need more time . . . it could be several weeks, it could be months."

"Inspections continue well. . . . I think we should be encouraged," said Russian Ambassador Sergey Lavrov. "If somebody feels that time is running out, the question why should be asked from that particular country."

The council will continue to discuss the issue behind closed doors this week, but no decisions are expected. Blix and ElBaradei are scheduled to present another inspection update on Feb. 14.

Despite its position as the closest U.S. ally on the council, and its dismissal of Iraqi cooperation with inspections as a "charade," Britain today said it would welcome the delay. "We wish to hear further how the inspectors are getting on," said Britain's U.N. ambassador, Jeremy Greenstock.

South Africa, although not currently a council member, spoke for nonaligned nations in asking that inspectors be given "sufficient time to do what we agreed they should be doing in Iraq."

Although the Bush administration has cited South Africa as an exemplar in disarmament for deciding in 1989 to dismantle its nuclear weapons program under IAEA supervision, South African Ambassador Dumisani Shadrack Kumalo today noted that the disarmament process had taken two years.

U.N. Secretary General Kofi Annan added his own appeal for more time this morning. "I'm not saying forever," Annan said, "but they do need time to get the work done."

Despite tough talk from the United States, and repeated vows to launch a military attack without U.N. approval if necessary, senior U.S. officials have made clear the administration is not yet prepared to force the issue.

U.S. military forces massing in the Persian Gulf will not be fully deployed until late February at the earliest, and officials have said they still hold out hope of convincing a council majority that an attack is both necessary and justified.

The administration plans to engage in intensive diplomacy over the next several weeks to convince reluctant allies that the inspections should not be allowed to continue indefinitely.

"The president will be in touch with fellow heads of state and governments," Powell said, "and I will be in touch with my colleagues in the Security Council." When those consultations are through, he said, "we will determine what the next steps are."

Although it has little hope inspectors will find a "smoking gun" in Iraq, the administration plans to increase the amount of intelligence information it is providing them, officials said. The recent addition of helicopters to the inspections effort, they said, has increased U.S. confidence that information can be acted on quickly enough to prevent Iraqi efforts to move or conceal evidence.

In his presentation today, Blix cautioned that Baghdad's failure to respond did not prove the existence of weapons of mass destruction, "nor do they exclude that possibility." But he cited incidents of harassment and intransigence by Iraqi officials and Iraq's refusal to answer specific questions about biological and chemical weapons.

He sharply criticized Iraq for failing to make scientists available for private interviews, blocking flights of U-2 surveillance aircraft and refusing to provide a complete declaration of its weapons programs.

"Inspection is not a game of catch as catch can," Blix told the council. "It is a process of verification for the purpose of creating confidence. It is not built on the premise of trust. Rather, it is designed to lead to trust."

While noting that investigations were ongoing, Blix said some evidence suggests Iraq may be engaged in banned missile programs, and in developing prohibited chemical and biological warfare agents. A 12,000-page Iraqi declaration presented to the council in December did little to explain what happened to thousands of chemical munitions, more than 8,500 liters of anthrax and huge quantities of biological growth media Iraq has not accounted for.

Among new details revealed today, Blix said Iraq illegally imported 380 missile engines, as well as missile guidance and testing systems and chemicals used in the production of rocket propellant. Of special concern, Blix said, was Iraq's decision to rebuild equipment, destroyed by earlier inspectors in the 1990s, capable of producing rocket motors with a range "significantly greater" than the 93-mile limit permitted by U.N. restrictions on Baghdad since the Persian Gulf War.

In what he said "might well represent prima facie cases of proscribed systems" Blix said two Iraqi missiles, the Al Samoud 2 and the Al-Fatah, had already exceeded the U.N.-imposed limit in tests by as much as 20 miles, although "some further technical considerations need to be made before we reach a conclusion."

U.N. inspectors have also uncovered small, laboratory quantities of a mustard gas precursor called thiodiglycol, he said. Inspectors maintain that Iraq has never accounted for more than 100 tons of the chemical, which has no known civilian application in Iraq.

Blix and ElBaradei voiced frustration with Baghdad's failure to make Iraqi scientists available for unmonitored interviews. Blix said Iraq had provided him with an incomplete list containing the names of nearly 500 Iraqi scientists associated with Iraq's weapons programs, compared with a list of more than 3,500 individuals compiled during previous inspections.

In saying that IAEA inspectors had not uncovered any substantive evidence that Iraq had restarted a nuclear weapons program destroyed by inspectors during the 1990s, ElBaradei cast further doubt on the Bush administration's contention that Iraq had sought to import "high strength" aluminum tubes to produce nuclear centrifuges.

"Our analysis to date," he said, suggested that the tubes were being used to engineer conventional rockets.

ElBaradei also said that inspections of buildings and facilities that Bush and British Prime Minister Tony Blair suggested last fall were being used as nuclear weapons factories had turned up "no prohibited nuclear activities," and that "we do not have enough information" to confirm U.S. and British allegations that Iraq sought to import uranium from Africa in the 1990s.

Secretary of State Colin L. Powell said Baghdad has little time to comply with arms inspections before disarmament by force is the only option. Chief U.N. inspector Hans Blix, right, said cooperation often is "withheld or given grudgingly." At left is IAEA Director General Mohamed ElBaradei.Jeremy Greenstock, left, Britain's U.N. ambassador, confers with U.S. Ambassador John D. Negroponte, who said that the Iraqi government was repeating its "denial and deception." Mohammed Douri, Iraq's ambassador to the United Nations, listens to Hans Blix's testimony before the Security Council.