Julian Assange, the founder of WikiLeaks, received a significant victory in his fight against extradition to the United States as London’s High Court deemed U.S. assurances regarding his case inadequate, granting him a full appeal hearing on Monday.

In March, the High Court provisionally gave Assange, 52, permission to appeal on three grounds. But it gave the U.S. the opportunity to provide satisfactory assurances that it would not seek the death penalty and would allow him to seek to rely on a First Amendment right to free speech in a trial.

In a short ruling, two senior judges said the U.S. submissions were not sufficient and said they would allow the appeal to go ahead.