It blocked last night's planned first departure of asylum seekers from Heathrow bound for the African nation.
The government says it expects to overcome legal challenges.
However Geoffrey Robertson QC - who helped bring the case before the court - says that isn't the only option the government has.
Nine protesters were arrested for blocking the road to an immigration centre near Heathrow where the asylum seekers were based.
Activists from Stop Deportations lay in the road at the Colnbrook Immigration Removal Centre.