Iraq threatened Wednesday to take action against U.N. weapons inspectors unless sweeping U.N. sanctions are lifted immediately.

The threat comes a day after reports that a U.S. Army laboratory found traces of VX, a deadly nerve agent, on Iraqi warheads. Iraq acknowledges experiments with VX but says its scientists never succeeded in transforming the agent into a weapon.If true, though, the finding could undermine efforts by Russia, France and China to end the seven-year inspection program and lift sanctions imposed after Iraq invaded Kuwait in 1990.

The Iraqi statement, signed by President Saddam Hussein and others, warned Iraq would reconsider its relations with inspectors if the sanctions were not lifted. The statement said Iraq would follow through on a threat of "grave consequences" it made May 1.

"When other means to lift the sanctions fail due to the hostility and evil of some parties, there will be no alternative to the strategy . . . to get rid of the unfair embargo," it said.

Iraq has the right to get "the sanctions lifted completely and comprehensively without delay and without conditions," it said.

Iraq has never spelled out what that strategy entails. But since May, it has threatened to take action against U.N. weapons inspectors whom it accuses of being British and American spies.

In Washington Pentagon spokesman Kenneth Bacon said the nerve gas evidence will make it impossible for the United Nations to lift the sanctions against Iraq at this time.

The information is important because Iraq has denied that it was ever able to produce VX in significant quantities or in a stable state, which would allow it to be stored for potential later use on weapons, Bacon said.

"So if this finding is borne out, it will mean that the U.N. Special Commission has found evidence that they (Iraqi officials) were not telling the truth and that confirm the long suspicions that the U.N. Special Commission has had. That's why it's significant," Bacon said.

The chief U.N. weapons inspector, Richard Butler, was to brief the Security Council later Wednesday on results of an analysis by the U.S. Army laboratory at Aberdeen, Md.