International Boxing Assocation (AIBA) President Gafur Rakhimov has responded to calls for him to resign from England Boxing by accusing chairman Caspar Hobbs of a "shocking" lack of respect for his fellow members within the governing body.
Hobbs claimed the "leadership of the organisation needs to be considered" and that it was time for Rakhimov "personally to think about the actions you can take to help resolve the issues faced by the sport".
His letter was sent to the AIBA President after the International Olympic Committee (IOC) launched an inquiry into the governing body and froze planning for the sport at Tokyo 2020.
Rakhimov has since issued a stinging response to Hobbs, claiming he was "surprised and disappointed" by the contents of the letter from the England Boxing chairman.
The 67-year-old, elected President of AIBA against the wishes of the IOC last month owing to his inclusion on a United States Treasury Department sanctions list as "one of Uzbekistan's leading criminals", also accused Hobbs of being deliberately misleading.
"I did hear about your letter while traveling last week, as it was apparently forwarded to media at the same time you sent it to me," Rakhimov writes in his letter to Hobbs, seen by insidethegames.
"Personally, I prefer to discuss AIBA matters directly with AIBA members as I feel that this is a more correct way to communicate but that is of course your choice.
"Leaving aside means of communication, I am surprised and disappointed with the contents of your letter and I do not at all 'recognise the spirit' in which you wrote the letter.
"In fact, it is a bit shocking that you have shown the lack of respect to all of your fellow Presidents in the AIBA National Federations, who by a very strong majority made their well-informed decision at our Congress just a little more than a month ago."
The IOC publicly stated for the first time recently that Rakhimov was one of the major problems the organisation has with AIBA.
IOC President Thomas Bach admitted his inability to "exercise his full function" as President of AIBA owing to his inclusion on the list, which prohibits travel to certain countries, was a key concern.
Rakhimov has previously hinted he could stand aside if the problems with the IOC continue.
The Uzbekistani official has promised he will not jeopardise boxing's Olympic future but has given no indication that he plans to step down.
Rakhimov reiterates in the letter to Hobbs that AIBA has made improvements in governance, judging and finances - three of the areas of concern outlined by the IOC - since he became interim President in January of this year.
England Boxing cast doubt on the assertions made by AIBA, however, claiming it is "clear that these measures have not been sufficient to address the deep-rooted issues that exist".
In response, Rakhimov questioned why England Boxing had not raised similar concerns "when the AIBA’s standards across all these areas were questionable and far from the good level we have now established".
"Mr Hobbs, I do not question your motives or your dedication to our sport," Rakhimov added.
"At the same time, I simply do not understand why you feel a need to question the commitment and the ability of a newly elected AIBA leadership – and even less why you feel a need to communicate it widely in an uninformed and biased way.
"We have made huge progress in the past 12 months, but we have still many important things to do.
"We can do this faster and better if we work in a supportive and unified way, and I will spend all my available time completely focused on the further development of our beloved sport.
"It would be appreciated if you did the same."
The letter marks an escalation of the row between AIBA and England Boxing, which publicly backed Rakhimov's rival Serik Konakbayev in last month's election.
Officials from the national governing body have grown frustrated at the repeated denials from AIBA and Rakhimov following the decision of the IOC Executive Board in Tokyo.
England Boxing did not wish to comment on the letter but a source told insidethegames they were surprised at AIBA appeared to refuse anything was wrong and the correspondence from Rakhimov had been placed in the public domain so quickly.
IOC President Thomas Bach assured athletes an Olympic boxing competition will still take place at Tokyo 2020 despite the issues with AIBA, claiming the IOC "wants to have a boxing tournament at the Games in Tokyo and we will make all efforts to have it".
The statement from the IOC Executive Board has caused concern in the amateur boxing world, however, as final confirmation on whether there will be an Olympic boxing event - and who will organise it - is not likely to be made until the Session in Lausanne next June, just over a year before the start of Tokyo 2020.
There is also not yet a qualification path in place for athletes.
A committee led by IOC Executive Committee member and United World Wrestling President Nenad Lalović tasked with leading the inquiry, which could lead to AIBA losing the right to organise the Olympic boxing tournament, will conduct the investigation over the coming months before reporting its findings next June.