The controversial technology looks set to be approved for use in the nation's food production channels, further to a risk assessment conducted by the Food and Drug Administration (FDA) earlier this year.
One of the aspects of FDA's plan that has invited significant opposition is that the labeling of meat and milk products from cloned animals would not be required.
The California Cloned Food Labeling Act (SB 63) aimed to allow the state's consumers the freedom of informed purchasing if the controversial technology is approved for use in the nation's food production channels.
However, Governor Schwarzenegger said he could not sign the bill as it is pre-empted by federal law, which governs labeling on a national level.
But consumer advocacy groups this week wrote to the Governor, claiming that this reasoning is "legally unsound, disingenuous and inaccurate".
"Federal law applies only to meat, not dairy products. The Governor's veto only referred to the federal meat labeling law, a tacit acknowledgement of this fact," stated the Center for Food Safety (CFS) and Consumers Union (CU).
"Dairy products derived from cloned animals will be the first such food products to reach California markets, and will make up the vast majority of the cloned food market. Dairy products are thus the primary target of SB 63," they wrote.
There are two federal laws that address meat labeling, but these do not preempt cloned meat labeling in California, they said. "Neither of these laws even mentions cloned meat, so they simply don't apply," said Rebecca Spector, West Coast director for CFS.
The two groups pledged to work with legislators to help introduce a similar cloned food labeling bill in California next legislative session, and called on the Governor for his support.
According to California State Senator Carole Migden, who introduced SB 63 in April this year, "People have the right to know if food is organic, if it contains pesticides or growth-promoting hormones, or if it's from cloned or natural-bred animals. Consumers certainly don't want to wrestle with moral issues like cloning while they're doing the family grocery shopping".
A recent national survey commissioned by the International Food Information Council (IFIC), found that 50 percent of American consumers have an unfavorable view of cloning, while 28 percent remain neutral.
And a recent survey by the Consumers Union found that 89 percent of Americans want food from cloned animals to be labeled.
Despite concerns raised by consumer groups and even industry, meat and milk from cloned animals are poised to enter the American food chain.
In December FDA issued draft guidance on the use of the practice in food production. According to its assessment of the available scientific evidence, the agency said there are no additional safety risks posed by the technology when compared to other assisted reproductive technologies currently in use in US agriculture.
The agency this week told FoodNavigator-USA.com that it is in the process of updating its cloning risk assessment (RA) and reviewing public comments.
"There is no estimated timeframe on when this will be finished," it said.
Cloning is also the focus of an amendment to the 2007 Farm Bill - Amendment 3524. Introduced by Senators Mikulski and Specter, this calls for more information on food products from cloned animals, with specific focus on elements that have not been addressed by FDA's initial risk assessment.
The amendment calls for studies that would evaluate the health effects of allowing the commercialization of milk and meat from cloned animals.
It also asks for an evaluation of the costs of this action, and its impact on overseas markets, which may ban exports from the United States.