Telemarketers will be required to transmit their telephone numbers and other caller-ID information under new rules that take effect on Thursday. The new regulation should make it easier for consumers with caller-ID equipment to screen out unwanted telephone sales calls and report those who are ignoring requests to be left alone, the Federal Trade Commission said. Along with their telephone numbers, telemarketers will be required to transmit their names to caller-ID readers where technically possible, the FTC said. Some telephone companies are not yet equipped to handle caller names. Telemarketers may alternatively transmit the names and phone numbers of the companies for which they are selling products, the FTC said. The new rule should make it easier for consumers to call telemarketers back and ask to be left alone, according to the Direct Marketing Association, a trade group. The FTC tightened telemarketing regulations last year, creating the tremendously popular Do Not Call registry, which forbids telemarketers from calling households that do not want to hear from them.