Falwell also said the terrorist attacks on the U.S. were "probably what we deserve."
The conservative minister made his remarks on "The 700 Club," the popular religious show on the Christian Broadcasting Network hosted by Pat Robertson. Robertson immediately said, "Jerry, that's my feeling. I think we've just seen the antechamber to terror."
In his apology, Falwell said his comments were ill-timed, insensitive and divisive at a time of national mourning. President Bush had called the minister's statement inappropriate.
"In the midst of the shock and mourning of a dark week for America, I made a statement that I should not have made and which I sincerely regret," Falwell said.
He added: "I want to apologize to every American, including those I named."
During his "700 Club" appearance, Falwell blamed the devastation on pagans, abortionists, feminists, homosexuals, the American Civil Liberties Union and the People for the American Way.
"All of them who have tried to secularize America, I point the finger in their face and say, 'You helped this happen,'" he said.
Falwell, a Baptist minister and chancellor of Liberty University in Lynchburg, Virginia, also expressed a belief shared by other evangelicals that divine protection is withdrawn from nations that violate God's will.
However, some Christian thinkers warned there was no way to know which sin led to which punishment. On Monday, Falwell agreed.
"When I talked about God lifting the curtain of protection on our nation, I should have made it very clear that no one on this Earth knows whether or not that occurred or did not occur," he said.
He said if the destruction was a judgment from God it was a judgment on all sinners, including himself.
Falwell said no one from the evangelical community or the White House pressured him to apologize.
However, he said a White House representative called him Friday while he was driving to the National Cathedral memorial service in Washington, and told him the president disapproved.
Falwell said he told the White House that he also felt he had misspoken.
Falwell made his apology minutes after Robertson's Christian Broadcasting Network released its own statement calling Falwell's on-air remarks "severe and harsh in tone and, frankly, not fully understood" by Robertson and his two co-hosts.
During last week's broadcast, Robertson had agreed when Falwell said, "God continues to lift the curtain and allow the enemies of America to give us probably what we deserve."
Angell Watts, a spokeswoman for Robertson's network, did not return calls seeking comment.
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