The US Food and Drug Administration (FDA) has imposed a new requirement that all Chinese products containing milk be certified as having no melamine before they are allowed into the country, the Wall Street Journal reported. In a directive to its field operations, the FDA said it was stopping a long list of products at the port of entry. The list ranges from baby foods to chocolates to pet food. The FDA said the products will not be released to importers without third-party verification that they contain no melamine or cyanuric acid, a melamine derivative. The FDA said it has found both melamine and cyanuric acid in some Chinese products containing milk. More than a dozen countries in Asia and Europe have found melamine in dairy products from China.