Bring it.

Food and milk from the offspring of cloned animals may already have entered the U.S. food supply, the Food and Drug Administration said on Monday, but it would be impossible to know because there is no difference between cloned and conventional products.

The FDA said in January meat and milk from cloned cattle, swine and goats and their offspring were as safe to eat as products obtained from traditional animals. Before then, farmers and ranchers had followed a voluntary moratorium that prevented the sale of clones and their offspring.

"It is theoretically possible" offspring from clones are in the food supply, said Siobhan DeLancey, an FDA spokeswoman. "I don't know whether they are or not. I could imagine there are not very many of them."

Proponents, including the Biotechnology Industry Organization, say cloned animals are safe and a way to create animals that produce more milk and better meat and are more disease-resistant. There are currently an estimated 600 cloned animals in the United States.