A Brazilian judge on Wednesday suspended the preliminary license for the Belo Monte hydroelectric dam, a controversial project in the heart of the Amazon rainforest, citing “danger of irreparable harm,” reports the Amazon Watch, an NGO that has been campaigning on the issue. The move comes just days after a high-profile visit by James Cameron, director of the box office hit Avatar, and Sigourney Weaver, one of the stars of Avatar, to indigenous communities potentially affected by the dam.

Judge Antonio Carlos de Almeida Campelo also cancelled the construction auction for the project scheduled for April 20 and ruled that IBAMA, Brazil’s environmental agency, refrain from issuing a new license for the project.