A triple veto by the United States, Britain and France blocked passage of a U.N. Security Council resolution that deplored the U.S. downing of two Libyan MiG-23 jets over the Mediterranean Sea.

The 15-nation council Wednesday voted 9-4, with two abstentions, for the resolution presented by non-aligned nations. But the vetoes prevented passage of the measure, which was toned down from a full condemnation of the Jan. 4 incident.Nine votes are required to pass a resolution but a negative vote, or a veto, by any of the five permanent members of the Security Council - the United States, the Soviet Union, China, France and Britain - can block its passage.

Canada cast a negative vote along with the United States, Britain and France. Brazil and Finland abstained.

Voting for the measure were China, the Soviet Union, Algeria, Nepal, Senegal, Yugoslavia, Colombia, Malaysia and Ethiopia.

The last time the United States, Britain and France joined together to veto a Security Council resolution was in April 1986 when the body was asked to condemn the U.S. bombings of the Libyan cities of Tripoli and Benghazi.

Non-aligned nations had sought a strong condemnation of the United States, but opposition from some Security Council members forced several modifications to soften the resolution's language.

The toned-down version urged the council to "deplore the downing of the two Libyan reconnaissance planes by the armed forces of the United States of America."

Libya's U.N. ambassador said on Thursday West German firms helped build the disputed Rabta chemical plant which is at the center of a row with the United States.

"The West Germans did help us, not only on this plant but other plants also," Ambassador Ali Treiki said on the CBS television show "This Morning."

But he maintained that the plant was designed to produce medicines only. Washington says it is a chemical weapons installation and that West German firms helped build it.

After more than a week of denials, Bonn acknowledged on Tuesday that there were grounds for the U.S. accusations, announced a tightening of export controls and ordered several West German firms to suspend exports to Libya.

Treiki also said Libya would sign any international accord banning the use of chemical weapons and allowing surprise on-site inspections of chemical plants.