A plan by Rupert Murdoch's News Corp. to buy controlling interest in Australia's domestic news service and its only newsprint maker has been frozen by a federal court decision. The court upheld an interim injunction granted last week to antitrust regulators who oppose News Corp.'s plan. The Trade Practices Commission contends that Murdoch's planned acquisition of about 80% of the shares of Australian Associated Press Ltd. and 90% of Australian Newsprint Mills Holdings Ltd. would violate the Trade Practices Act, which deals with market dominance. Murdoch's international media company already controls nearly 60% of the Australia's daily newspaper market. The court hearing on the matter will probably resume in mid-February, a commission official said.