We have no weapons of mass destruction. Your move, Mr Bush

7 files, 11,807 pages, 352 appendices, 529 megabytes on CD-Roms and one message from Iraq ...

Iraq yesterday threw down a challenge to the United States, announcing that it had no weapons of mass destruction as it handed over more than 12,000 pages of information on its nuclear, chemical, biological and missile programmes to the United Nations a day ahead of the deadline set by the Security Council.

The Iraqi official in charge of the declaration, Lieutenant General Hossam Mohammed Amin, said the mass of material would "answer all the questions which have been addressed during the last months and years". But he added: "I reiterate here Iraq has no weapons of mass destruction."

A UN plane took off from Saddam International Airport this morning carrying three sets of voluminous documents. The plane later landed at Cyprus, from where the huge declaration was transferred to other flights, taking two sets to the UN headquarters in New York and one to the UN nuclear agency in Vienna.

The US insists it has intelligence which will show Baghdad is lying. Once Iraq's report to the UN is analysed, any evidence that it has concealed nuclear, chemical or biological weapons, or hidden medium- or long-range missiles, could trigger the war many senior members of the Bush administration have been seeking.

According to diplomatic sources, Washington does not want to show its intelligence on Iraq to all the UN weapons inspectors, only the ones it trusts – a stance which could set off a row with the UN. If the US gets its way, however, it is possible that "surprise" inspections could be carried out in Iraq before the end of the month, designed to trigger war within weeks.

In his weekly radio address to the US public, taped before Iraq's report was handed over, US President George Bush raised pre-emptive suspicions that the information would pass muster. In the past, he said, Saddam Hussein admitted to "a massive biological weapons programme" only after being confronted with evidence.

"Thus far we are not seeing the fundamental shift in practice and attitude that the world is demanding," said Mr Bush. General Amin retorted for Iraq: "I think if the United States has the minimum level of fairness and braveness, it should accept the report and say this is the truth."

President Saddam, meanwhile, opened a surprising new front in the propaganda war, issuing an open letter to the Kuwaiti people in which he apologised for his 1990-1991 occupation and urged them to struggle against foreign armies.

"We apologise to God for doing anything that angers Him," said the letter, read out on Iraqi state television last night. "If that had happened in the past, and we don't know about it, but we were considered responsible for it, on this basis we apologise to you."

But the Iraqi president also assailed Kuwait's leaders, saying they were working with foreigners to attack Iraq, and referred to Kuwait, where thousands of US troops have been based since the 1991 war, as being under American occupation. At about the same time, Iraqi government vehicles bearing boxes holding the arms documents entered the UN compound on Baghdad's outskirts, and officials unloaded the material to hand over at a private meeting with UN officials inside. The 12,000 pages and CD-Roms of technical detail now shift the Iraq crisis into a new stage.

After the material reaches New York and Geneva late today, the thick reports on past weapons programmes will take experts weeks to analyse and arms inspectors months to verify inside Iraq. Data that might help others to produce chemical, biological or nuclear weapons will be weeded out, possible delaying the handover of the material to the Security Council's member nations. "We would advise the council that these should not be circulated to anybody," chief UN weapons inspector Hans Blix said of the sensitive sections.

After a two-day holiday break marking the end of the Muslim holy month of Ramadan, the inspectors resumed their work yesterday, visiting two sites south of Baghdad previously inspected in the 1990s.