VICTORIA has been ordered to remove cattle from the Alpine National Park after federal Environment Minister Tony Burke ruled it should have sought his approval before launching the state's controversial grazing trial.

Declaring that cattle must be removed by April 8, Mr Burke said the Baillieu government had repeatedly failed to answer key questions about the trial since releasing about 400 cattle into the park in January. He said the state had failed to provide a copy of the research proposal or explain what steps it was taking to protect sensitive areas.

''For reasons I do not really comprehend, the Victorian government decided they didn't really care if they were on the right side of the law,'' he said.

''The information that has come back from the Victorian government is a joke … For something that is meant to be a university research project, they have provided information that wouldn't pass as a high school science project.''

Mr Burke's ruling means cattle cannot be released into the park before his department assesses if they would have a significant impact on protected wetlands and endangered species, such as the alpine tree frog. It effectively restores a 2005 Bracks government ban based on advice that grazing harmed the environment and was not a significant factor in reducing bushfires.