"We are party to the Biological Weapons Convention from 1972," State Department spokesman Philip Reeker said Monday. "We think this is very important. We strongly support that convention.
"But as we've said for some time now, more work needs to be done on steps taken to strengthen that, to respond to the threats that are out there," he said.
Discussions on how to enforce the treaty are taking place this week in Geneva.
American envoy Donald A. Mahley was expected to tell negotiators Wednesday that the Bush administration supported the convention but feared the enforcement rules would be burdensome to some universities and industries and might expose American businesses to commercial theft.
China and Russia on Monday appealed for cooperation on treaty enforcement. Libya, Cuba, Iran and Pakistan oppose the proposed enforcement language, while the United States' traditional partners in Europe and Latin America support it.
The Bush administration is already facing criticism from European nations for rejecting initiatives on climate change and small arms trade.
This week it stood on the sidelines as 178 countries approved a deal to salvage the Kyoto Protocol on global warming, which Mr. Bush has called "fatally flawed" because it targets only developing countries and could cost American jobs.
Reeker Tuesday tejected the notion that the germ weapons issue was another example of the United States walking away from multilateral agreements.
"We haven't walked away from anything," he said, contending the country remains involved in numerous multilateral organizations and agreements and has the right to voice concerns when it feels proposals will not work to attain the treaties' goals.
"The United States has an unparalleled record of, first, supporting multilateral nonproliferation objectives and efforts," he said, citing the Nuclear Nonproliferation Treaty and the Chemical Weapons Convention in addition to the germ weapons convention.
The treaty, ratified by 143 nations, prohibits the development, production and possession of biological weapons. Negotiators hope to develop enforcement rules by November.
The Clinton administration had supported the protocol.
The Biological Weapons Convention requires signatories " never in any circumstances to develop, produce, stockpile or otherwise acquire or retain" biological weapons or vehicles for their delivery.
In 1976, federal agencies reported that they were in compliance with the treaty. But the lack of verification led to efforts over the years to try to bolster enforcement.
Domestic opponents contend efforts to enforce the treaty would violate the U.S. Constitution. A Cato Institute policy brief says any attempts to check on what U.S. companies were manufacturing could impinge upon "the right to privacy reflected in the Fourth Amendment, the separation of powers principle found in the appointments clause, and the right to intellectual property found in the Fifth Amendment."
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