Human rights organisation Amnesty International have criticised Newcastle's potential takeover by the Saudi-backed consortium PCP Partners in a letter to Premier League chief executive Richard Masters.
Paperwork on the Newcastle deal is being finalised after an agreement was found on Monday between Mike Ashley and PCP Capital Partners.
Amnesty UK director Kate Allen wrote to Masters to express concern about Saudi Arabia's human rights record.
"So long as these questions [about Saudi Arabia's human rights record] remain unaddressed, the Premier League is putting itself at risk of becoming a patsy of those who want to use the glamour and prestige of Premier League football to cover up actions that are deeply immoral, in breach of international law and at odds with the values of the Premier League and the global footballing community," she wrote.
"The Crown Prince has been using sporting events and personalities as a means of improving the Kingdom's reputation following the grisly murder of the journalist Jamal Khashoggi -- widely believed to have taken place with his approval.
"Such positive associations with sporting events also distract attention from Saudi's appalling human rights record, including the imprisonment and torture of women human rights defenders."
Once the deal is finalised, Yasir Al Rumayyan, a close friend of Mohammed bin Salman, the Crown Prince of Saudi Arabia, will be the new chairman.
Amnesty International have criticised Saudi Arabia's human rights record several times in the past and the country has been accused of using sports as a means of distracting from the abuses.
Sources have told ESPN that should the deal go through the new owners will go after a big-name manager with Massimiliano Allegri and Mauricio Pochettino among their preferred candidates and Edinson Cavani is also a transfer target.
One of the Premier League's largest overseas broadcast partners, beIN Sport, have also written to the top-flight clubs to ask for their co-operation in the investigation of the proposed takeover.