Phone numbers used by French President Emmanuel Macron and top members of his government are among the potential targets for the Pegasus spyware supplied to several governments worldwide, the NGO that leaked the list of numbers said Tuesday.

"We found these numbers but we obviously couldn't do a technical analysis of Emmanuel Macron's phone" to determine if it had been infected with the malware, the head of Forbidden Stories, Laurent Richard, told LCI television.

"But it shows in any case there was an interest in doing it," he said.

"If this fact is established, it's obviously very serious," a spokesman for Macron's office said.

Forbidden Stories, a Paris-based media nonprofit, and Amnesty International initially had access to the leaked numbers, which they then shared with media organisations including The Washington Post, The Guardian and Le Monde.

Macron's phone number was among some 50,000 believed to have been identified as people of interest since 2016 by clients of the Israeli firm NSO, developer of the Pegasus cyber-surveillance technology, the reports said.

Activists, journalists and politicians around the world were targeted, prompting fears of widespread privacy and rights abuses.

The news outlets with access to the leak said more details about those who were compromised would be released in coming days.