Apple Inc.'s talks with Hyundai Motor Group have broken down without an agreement for the South Korean auto giant to assemble vehicles for the iPhone company, Hyundai affiliates said Monday. In regulatory filings, Hyundai Motor Co. and Kia Corp. said they are "not in talks with Apple over developing an autonomous vehicle." The two auto makers have fielded multiple requests from other firms to jointly develop autonomous electric vehicles, though no initial steps have been determined, according to the regulatory filings. The companies had held talks with the Cupertino, Calif., technology giant about a deal for Hyundai subsidiary Kia to build vehicles for Apple in Georgia, The Wall Street Journal reported last week. The prospect of an auto partnership had sent the Korean companies' stocks soaring this year, igniting investor enthusiasm after both Kia and Hyundai had suffered years of slumping car sales.