The organisation said it would create a commission that will "operate at arms-length from Oxfam" and be given access to the charity's records and interview staff in an attempt to stamp out abuse.
U.K. International Development Secretary Penny Mordaunt has warned that British government funding to the group - some 31.7 million pounds ($43.8 million) in 2016-17 - is at risk unless it comes clean about the allegations.
Oxfam have since announced that a comprehensive plan of action will be put into place to strengthen safeguarding systems across the organisation.
"We are committed to proving that we deserve the confidence of the United Kingdom public", the charity said.
South African Nobel laureate Desmond Tutu, British actress Minnie Driver and Senegalese musician Baaba Maal have all resigned as Oxfam celebrity ambassadors in the wake of the sexual misconduct allegations and Britain's charity regulator has launched an investigation.
"This was with an honourable, mature woman, who was not an quake victim nor a prostitute".
Oxfam's regional director for Asia Lan Mercado earlier this week told the BBC she was aware of cases of sexual abuse involving staff in Bangladesh, Nepal and the Philippines between 2009 and 2013.
She said ministers "reserve the right to take whatever decisions about present or future funding to Oxfam, and any other organisation, that we deem necessary".More news: Mikaela Shiffrin misses out on slalom medal at Olympics
She added that "hundreds of good, fearless and compassionate people working for Oxfam around the world" had been "poorly served by Oxfam's leadership team".
Oxfam Ireland has said it will play a "leadership role" as the global charity works to introduce reforms to "root out any form of abuse".
"I think (her criticism) was very unbalanced, and ironically didn't give enough credit to the very work that she promoted", he told the paper.
He said: "I don't think (Oxfam) wanted to promote a sensation and damage the delivery of that programme".
Oxfam has come under fire for failing to inform other aid organisations of the allegations against its staff including Van Hauwermeiren, who went on to work for French charity Action Against Hunger in Bangladesh.
"All I can tell you about this terrible revelation about Oxfam is that I am devastated", she wrote on Twitter.