British Gymnastics chief executive Jane Allen has admitted to feeling “appalled and ashamed” by escalating allegations of bullying and abuse within the domestic sport.

Allen has come under increasing pressure to resign after being accused of presiding over an organisation which has consistently failed to adequately address complaints.

The growing scandal reached the current world-class programme on Thursday with sisters Becky and Ellie Downie issuing a statement that described “an environment of fear and mental abuse”, and an atmosphere in which abuse was “completely normalised”.

In a letter issued to members and seen by the PA news agency, Allen saluted the “bravery” of those like the Downies who have spoken out, and vowed their words will prove a catalyst for real change.

Allen wrote: “Any mistreatment of gymnasts is inexcusable. It is vital that concerns are made public, whether that is through the media or our processes.

“I pay tribute to those who have spoken out – their bravery will help drive change within gymnastics.

“Personally, I am appalled and ashamed by the stories I have heard. We have worked hard to put in place a mandatory Positive Coaching Behaviours programme and an Integrity Unit to investigate allegations of emotional abuse and bullying.

“While those have been audited and accredited by leading experts in the field, most recently in May of this year, we clearly need to do more. And quickly.”

British Gymnastics has committed to an independent review of its procedures, with the results expected in the autumn.

Allen added: “The right thing is to ensure that an independent eye looks at the complaints raised this week and the systems we have in place.

“To be clear, the Review’s conclusions and recommendations will be the QC’s alone. You have my commitment that British Gymnastics will do everything needed to support the Review but will not seek to influence it in any way.

“This is extremely important and will help us better understand barriers to reporting misconduct in our sport and where we need to provide greater guidance to our members and the wider gymnastics community on what is acceptable and what is not.

“The experiences of gymnasts highlighted this week have described fundamental issues within the gymnast-coach relationship. I expect the Review and recommendations that come from it to address this and help provide clarity that helps protect gymnasts at every level.

“We are determined to get to the bottom of these issues and change gymnastics for the better.”

Elissa Downie released a statement on Thursday
Ellie Downie released a statement on Thursday (Peter Byrne/PA)

Allegations of bullying and abuse at all levels of the sport continue to mount, with one member of the Rio 2016 team, who wishes to remain anonymous, claiming a complaint that she made to the governing body eight months ago is yet to be addressed.

Meanwhile former British rhythmic champion Nathalie Moutia has accused the governing body of failing to consider the long-term impact on young athletes.

Moutia said the abuse she suffered as a young athlete “ruined my life”, said her complaints to British Gymnastics were ignored, and added: “The fact it’s still going on today – I just don’t understand how it can continue.”

The Cartoon Network announced the suspension of its deal with British Gymnastics, which allows the governing body to use its ‘Powderpuff Girls’ imagery.

The company said: “In light of the recent allegations and while investigations are ongoing, we have suspended our licensing agreement with British Gymnastics.”