Gordon Elliott will not be permitted to have runners in Britain until the conclusion of an Irish Horseracing Regulatory Board investigation into an image on social media that showed the Grand National-winning trainer sitting on a dead horse on his gallops.
Racing authorities in Britain and Ireland have condemned the image, which Elliott confirmed in a statement on Sunday evening was genuine, apologising "profoundly for any offence that this photo has caused", while seeking to explain what he said was the context of events that led to the photograph.
The IHRB has already launched a full investigation - and while Elliott is licensed in Ireland, the British Horseracing Authority said it was "appalled" by the image and was "considering its own regulatory options", but has now acted.
A statement on Monday evening said: "The British Horseracing Authority will not allow the Irish trainer Gordon Elliott to race horses in Britain whilst the Irish authorities investigate an image that appeared on social media over the weekend.
"The trainer admitted the photo was genuine and apologised for his actions.
"The BHA, which regulates racing in Britain, will use powers under its own rules to refuse to allow horses trained by Mr Elliott to race in Britain pending consideration of the outcome of the Irish investigation.
"The action taken by the BHA recognises that Mr Elliott is licensed in Ireland, whose regulatory body, the IHRB, is carrying out its own investigation.
"However, Mr Elliott has entered horses to race in Britain, from which point the British rules of racing apply to him.
"The decision to refuse to allow horses trained by Mr Elliott to run in Britain is therefore an interim decision which the BHA regards as proportionate in these circumstances."