Lionel Messi has been condemned by the Human Rights Foundation, who accuse him of "partying with oppressors" in his recent visit to Gabon.
The Barcelona star was photographed with Gabon dictator Ali Bongo after helping lay a foundation stone for a planned new venue for the Africa Cup of Nations finals in 2017, while he also visited a state-run hospital and a restaurant owned by the Bongo family.
While the Gabon government has strenuously denied reports that Messi was paid a seven-figure sum to attend the country in July, he has nonetheless been criticised for showing public support for the Bongo regime.
The controversial leader of the country has been accused of electoral fraud in the past, as well as certain human rights abuses, including the refusal to sanction investigations into the killing of children.
"In providing PR services to Gabon's Bongo family, Lionel Messi has seriously undermined the credibility of his own charitable foundation," said Human Rights Foundation president Thor Halvorssen.
"Whereas Messi claims to support children's rights, and even serves as a Unicef ambassador to promote youth education, he has endorsed a kleptocratic regime that refuses to investigate the ritual murder of children in Gabon.
"Messi's trip is part of the Bongo family's PR campaign to promote the 2017 Africa Cup of Nations, which Gabon will host at enormous expense despite the fact that the Bongo family's embezzlement has left 20 per cent of the population to live on less than $2 per day."
HRF chief strategy officer Alex Gladstein added: "It's shocking, given the recent public humiliation endured by Jennifer Lopez, Mariah Carey, and Kanye West, that Messi's management and the athlete himself would consider putting his prestige at the service of a serial human rights abuser.
"If Messi wants to do good in Gabon, HRF recommends that rather than partying with oppressors, he release a statement in solidarity with the country's persecuted dissidents and environmentalists, and press the regime to investigate the ritual murders of children."
Bongo himself claimed during the visit that Messi's appearance was simply due to a promise he made in an earlier meeting in Barcelona.
"When I was in Barcelona a few years ago, I met Messi who had told me that he would come to visit me in Libreville," he said. "It's a promise he made me. He is a man of honour who just kept his word."