Washington ? The former chief U.S. weapons inspector in Iraq issued a broad critique of U.S. intelligence gathering Wednesday, saying that the U.S. government was simply “wrong” to conclude before the war that Iraq was maintaining major stockpiles of weapons of mass destruction.

Testifying before the Senate Armed Services Committee, David Kay said that contrary to earlier claims by President Bush and his Cabinet, Iraqi leader Saddam Hussein did not possess “large stockpiles” of chemical and biological weapons and was not actively pursuing nuclear weapons.

“There’s a long record here of being wrong,” Kay said, adding he believed that Bush and other U.S. officials, as well as U.S. allies, had based their beliefs on flawed intelligence. “It turns out we were all wrong,” he said.

Kay said the errors raise serious questions about intelligence-gathering methods. “We’ve got a much more fundamental problem of understanding what went wrong.”

Bush and top Cabinet officers, including Vice President Dick Cheney, frequently cited intelligence reports that Iraq possessed chemical and biological weapons and was developing nuclear weapons as justification for invading Iraq.

But Kay said Wednesday that the U.S. had failed to develop valid human intelligence sources inside Iraq during the past decade, relying instead on information gathered by United Nations weapons inspections from 1991 to 1998 and from other governments that shared information in what are called “liaison” arrangements. That information, he said, proved incorrect.

“I had innumerable analysts who came to me in apology that the world that we were finding was not the world that they had thought existed and that they had estimated,” Kay said of his intelligence colleagues. “Reality on the ground differed.”

Kay said that he, too, once believed that Iraq possessed weapons of mass destruction, but that the work of the Iraq Survey Group, which he directed until his resignation Friday, convinced him that Hussein had destroyed his weapons caches several years ago.

Those stockpiles, Kay said, were destroyed when Hussein realized they made him vulnerable to Western scrutiny. The Iraqi leader, he said, instead plotted to retain the scientists and equipment to quickly revive his weapons programs once outside scrutiny had eased.

Until Kay began to discuss his findings in the last week, the White House had insisted that the search in Iraq would produce evidence of weapons of mass destruction.

Tuesday, however, Bush began to back off assurances that such weapons would one day be unearthed in Iraq. Instead, the president said the war was justified because Hussein posed a growing threat.

In response to Kay’s Senate testimony, White House spokesman Scott McClellan said Wednesday, “It’s important that we let the Iraq Survey Group complete their work and gather all the facts they can. Then we can go back and compare what we knew before the war with what we’ve learned since. But that work is ongoing at this point.”