United Nations weapons chief Hans Blix says the recent discovery of empty chemical warheads in Iraq is not such a big thing. Mr. Blix met Friday with French President Jacques Chirac, who says France would not support any attack on Iraq without prior U.N. approval.

At a news conference, Mr. Blix suggested the newly discovered, empty chemical warheads are not, by themselves, sufficient reason for the Bush administration to launch a war on Iraq. "You better ask Mr. Bush himself," he said. "However, what I see from the American reaction is that they, too, would like to have a little further information about this. So I'm not so worried."

Mr. Blix said he is not certain whether Iraq mentioned the empty chemical warheads in its 1,200-page report submitted to the United Nations in December. Iraq says the warheads are in the report, but the spokesman for the weapons inspectors said Thursday they are not.

Mr. Blix and the head of the International Atomic Energy Agency, Mohamed ElBaradei, are to visit Baghdad this weekend, to press for further cooperation from the Iraqi government.

Their visit comes just one week before the January 27 meeting of the U.N. Security Council, where the two officials will present a preliminary report on the weapons inspections in Iraq. Both Mr. Blix and Mr. ElBaradei have said it will take several more months to determine whether Iraq is free of weapons of mass destruction.

Mr. Blix told a French reporter that intelligence information supplied by the United States and other countries is beginning to help inspectors in their search for hidden weapons sites. Still, Mr. Blix said he and Mr. ElBaradei need more intelligence information to help the inspectors do their job. At the same news conference, President Chirac said France would not participate in any military action against Iraq without U.N. approval.

Mr. Chirac told reporters only the U.N. Security Council can decide whether Iraq has violated U.N. weapons bans - and what to do if it has. His remarks Friday are the clearest declaration to date on France's conditions for participation in any attack on Iraq.