British actress Minnie Driver has withdrawn her support from Oxfam following allegations the charity tried to cover up the use of prostitutes by its staff in Haiti.
Ms Driver, who is best known for starring in 1997 film Good Will Hunting, said she had been "horrified" by the claims and would be stepping down as a celebrity ambassador after 20 years with the charity.
“All I can tell you about this awful revelation about Oxfam is that I am devastated,” the 48-year-old wrote on Twitter.
“Devastated for the women who were used by people sent there to help them, devastated by the response of an organization that I have been raising awareness for since I was 9 years old #oxfamscandal.”
Ms Driver, who had travelled to Cambodia and Thailand with the charity, said she would continue to fight economic and social injustice.
Responding to the announcement, a spokesperson for Oxfam said: "Her decision to step down as an Oxfam Ambassador saddens us deeply, but we also understand and respect her choice."
Ms Driver is the first celebrity to leave the international charity, which is headquartered in Oxford, UK, since an investigation by a British newspaper revealed senior Oxfam staff had paid prostitutes for sex in earthquake-hit Haiti in 2011.
Celebrity ambassadors and supporters of the charity include a whole array of British talent, including indie band Coldplay, Harry Potter actress Bonnie Wright and comedians Stephen Fry and Ruby Wax.
The UK's charity watchdog has launched a statutory inquiry to look into claims by The Times that Oxfam tried to cover up the findings of an internal investigation that found that aid workers had held sex parties with girls during the humanitarian relief mission.
One of the aid workers who admitted using prostitutes while working in Haiti was Oxfam’s country director Roland van Hauwermeiren. On Tuesday a former colleague of Mr van Hauwermeiren said that he had been sent home from a mission with another British charity for using prostitutes in Liberia.
The charity commission is investigating claims that he was able to get a job with Oxfam just two years after being dismissed from health charity Merlin.
On Monday Oxfam’s deputy chief executive Penny Lawrence resigned over the scandal, saying she took full responsibility for what had happened under her watch, while apologising for the “harm and distress” caused.
Oxfam now faces a battle to prevent other high-profile ambassadors from stepping down as well as making sure the UK government does not withdraw the £32 million (Dh163m) of funds it receives.
Britain’s international development secretary Penny Mordaunt is due to meet with investigators from the National Crime Agency to discuss the scandal.
“While investigations have to be completed and any potential criminals prosecuted accordingly, what is clear is that the culture that allowed this to happen needs to change and it needs to change now,” she said at a child protection summit in Stockholm.
Meanwhile, another international aid agency Medecins Sans Frontiers (MSF) revealed on Wednesday it had acted on 24 cases of harassment or sexual abuse last year.
The France-based NGO said it had dismissed 19 staff members as a result and handed out disciplinary measures to others.
"Even though reports of abuse have steadily increased, MSF is aware that abuse goes under-reported," the charity said in a statement.