Leaders of the six-member Gulf Cooperation Council signed two documents, the Al-Ula declaration, named after the Saudi city where the summit was held, and a final communique.
Those countries will meet in the Saudi city of Al-Ula, after Riyadh overnight re-opened its borders to Doha despite lingering enmity between the neighbours.
The ruling does not order the disclosure of the documents but the Open Society Justice Initiative described the order as a "crucial victory in addressing the Trump administration's shameful cover-up" of the murder.