New York — More than half the U.S. public says the White House has yet to make a clear case against Iraq, says a New York Times/CBS News poll released on Saturday.

The poll, published in Sunday's New York Times, also says that majorities want congressional and allied support for military action against Iraq, and that U.S. President George W. Bush's approval rating remains high, although it has slipped since July.

Of 937 adults interviewed by telephone last Monday through Thursday, 64 per cent said the Bush administration had not clearly explained its position concerning Iraq, and even 57 percent of those who said an attack was necessary now expressed that view.

Two-thirds said the nation needed to wait for allied support, against 25 per cent who said Iraq was such a huge threat the United States should act now.

Sixty-two per cent said Mr. Bush should be required to get congressional approval before taking military action against Iraq. That figure was down from 71 per cent who said so in a CBS News poll early in August.

Mr. Bush's approval rating stood at 63 per cent, down from 70 per cent in mid-July and the mid-80s last fall and winter.

As the anniversary of the Sept. 11 attacks near, just two out of five respondents said the government had done enough to protect them from another terrorist strike. The poll's margin of error was plus or minus three percentage points.

The Bush administration, which has been calling for "regime change" in Baghdad, has begun reaching out to world leaders, most of whom oppose unilateral U.S. military action.

Mr. Bush advisers said that when the president addresses the United Nations on the issue next Thursday he will challenge the world body to take quick, tough action to disarm Iraq.