The people concerned have been warned by Apple that their phone was targeted by this software which allows to access files, listen to conversations or track movements, say the information.
NSO Group indicated in a message sent to AFP that it had already suspended potentially affected customers "because of the seriousness of the charges", without however identifying them.
The group assures to have received "for the moment no information, telephone number or indication that the software of NSO was used in this business".
But he says he is ready "to cooperate with any competent governmental authority and to share all the information in his possession".
An international media collective revealed this summer that Pegasus had made it possible to spy on the numbers of journalists, politicians, activists or business leaders from different countries, including French President Emmanuel Macron.
But American diplomats seemed to have been spared, not least because Pegasus is, according to NSO, designed not to be able to be used on numbers starting with +1, the telephone code of the United States.
According to the Washington Post daily and Reuters, Pegasus was indeed used to infiltrate the iPhones of at least nine State Department employees based in Uganda or working mainly on issues related to East Africa.
Washington had added NSO Group to its list of banned companies in early November.
The iPhone maker, which recently filed a lawsuit in the United States against NSO Group asking to permanently ban the Israeli company's software on its devices, declined to comment on Friday.
Soon after the revelations this summer, he fixed a computer vulnerability exploited by Pegasus that allowed spying on people without users even having to click on trapped links or messages.
Apple had indicated at the time of filing its complaint that it would inform the "small number" of users who may have been targeted by this type of attack.
© 2021 AFP