Zimbabwe's High Court on Monday ruled that State Security Minister Owen Ncube had no power to order the internet shutdown which took place during last week's nationwide protests.
"It has become very clear that the minister had no authority to make that directive," judge Owen Tagu said in a case brought by human rights lawyers and journalists.
The shutdown occurred as the security forces cracked down on protesters following a wave of anti-government demonstrations which turned violent.
David Halimana, the lawyer representing the complainants, said the ruling meant "mobile network operators are with immediate effect required to give full and unrestricted access of internet to all their subscribers".
Halimana said that, in terms of the law, only the state president has powers to order an internet shutdown.