0600 GMT May 26, 2022
Contacted by AFP, the prime minister's office refused to confirm the reports in the online edition of daily newspaper El Pais and other media.
Paz Esteban, the first woman to head Spain's CNI intelligence agency, appeared before a parliamentary committee for questioning last week over the phone hacking scandal.
She confirmed that Catalan separatists had been spied on by the CNI but always with court approval, several participants at the meeting told Spanish media at the time.
Government sources, cited by the media, said the government had not been informed of the spying.
The scandal broke in April when Canadian cybersecurity watchdog Citizen Lab said the phones of over 60 people linked to the Catalan separatist movement had been tapped using Pegasus spyware after a failed independence bid in 2017.
It deepened after the government announced on May 2 that the phones of Sanchez and Robles were hacked by the same spyware, made by Israel's NSO group, in May and June 2021.
The affair has sparked a crisis between Sanchez's minority government and Catalan separatist party ERC. Sanchez's fragile coalition relies on the ERC to pass legislation in parliament.