It came after Hanan Meltzer, another court judge, noted that the governments of Rwanda and Uganda both denied having secret agreements with Israel to receive migrants.
The judge said it is essential to know what agreements exist so the deportees can be protected under their terms.
With the first deportations scheduled to begin next month, the first migrants who refused to leave were arrested a fortnight ago.
As part of the process, the Holot detention facility — where migrants were held by night but allowed to leave during the day — was closed last week. The migrants there were told to sign a statement promising not to move to cities like Jerusalem and Tel Aviv.
Two thirds of the African migrants in Israel are from Eritrea and many cited their desertion from the army there as grounds for their asylum applications.
Immigration authorities in Israel had decided these grounds were insufficient, but were ordered by a lower court two months to reconsider the deserters’ applications.
