Corporate partners of Oxfam have expressed major concerns about the safeguarding issues affecting the charity.
Companies including the retailers Marks & Spencer and Sainsbury’s, and the credit card company Visa, said they were contacting the charity to see how it was addressing safeguarding concerns in its international programmes after the recent scandals in Haiti and Chad.
This comes after allegations of sexual misconduct in the charity’s Haiti and Chad programmes, and claims that the charity failed to provide the full details of either case to the Charity Commission or the government.
Oxfam has since apologised "unreservedly" and announced a range of measures to strengthen its safeguarding policy, but has been threatened with having its UK government funding withdrawn and is the subject of a Charity Commission inquiry.
A spokeswoman for M&S said that the allegations were "very serious" and the retailer would "monitor the situation very closely as we seek to understand the steps that Oxfam is taking to address them and develop a robust safeguarding plan for the future".
A spokeswoman for Sainsbury’s said: "We’re extremely concerned by these deeply disturbing reports and are discussing with Oxfam as a matter of urgency."
A statement from Visa said: "At Visa, we are committed to the highest standards of professional and personal conduct, and we expect the same from our partners.
"We are engaged with Oxfam to understand what steps have been taken to address staff misconduct and ensure alignment with our own standards and values."
Spokeswomen for Heathrow Airport and the Co-operative Bank, which are also Oxfam corporate partners, said they were contacting Oxfam about the recent crisis.
But the bookseller Waterstones came out in defence of its partnership with the charity, saying it remained a "committed supporter".
The company said: "Waterstones remains a committed supporter of Oxfam. The work of the charity, as of its peers, is of great value. We listen to and seek to understand the assurances given by the Oxfam leadership."
The actor Minnie Driver also announced yesterday that she had stood down as a celebrity ambassador for the charity.
She said she would not be working with Oxfam in the future and would instead be devoting time to other international development charities.
"All I can tell you about this awful revelation about Oxfam is that I am devastated," Driver wrote on Twitter.
"Devastated for the women who were used by people sent there to help them, devastated by the response of an organisation that I have been raising awareness for since I was nine years old."
In a statement, Oxfam said: "Minnie Driver has been a devoted Oxfam supporter for many years and we are grateful for her commitment to ending global poverty. Her decision to step down as an Oxfam ambassador saddens us deeply, but we also understand and respect her choice.
"As an organisation, we are ashamed by the actions of some of our staff and are more committed now than ever to learn from our mistakes and ensure we uphold the highest levels of safeguarding standards in our work around the world."