Eng, a four-time Paralympian and Canada's captain, is a high-profile victim of a dispute between the IWBF and the International Paralympic Committee (IPC) which emerged in January.

The IPC said that wheelchair basketball was not complying with its classification rules and threatened the sport with removal from Tokyo 2020 if a May 29 deadline to implement an action plan was not met.

Wheelchair basketball has also lost its place at Paris 2024 but this could be reversed if the IWBF becomes "fully compliant" with the IPC Athlete Classification Code by August 2021.

Last month, the IPC pushed back the May 29 deadline to August 1 because of the coronavirus crisis.

In a statement today, the IWBF said they had released the first set of results from phase one of a classification eligibility reassessment process.

Seventy-five per cent of 134 submitted players have received decisions, the governing body said.

The rest are either still under review after further evidence was submitted, or are still pending as additional documents have not been received due to COVID-19 restrictions.

The first phase required all players in the 4.0 and 4.5 classes, from countries which have qualified for Tokyo 2020, to submit forms and medical evidence to verify that they have an eligible impairment.

Wheelchair Basketball Canada revealed that three of its players were deemed eligible but Eng, who was Canada's Opening Ceremony flagbearer at the Rio 2016 Paralympics, had failed the process.

"This is obviously not how I intended to end my international career and I'm disappointed to not be able to finish what I started with my team-mates next year in Tokyo," said Eng, who won Paralympic gold at Athens 2004 and London 2012 and the world title in 2006.

"At the same time, this sport has brought a lot to myself and my family and it's all the positives that I'm going to remember.

"I have been captain of the team since 2007 and am blessed to have enjoyed a great career that has spanned over three decades. 

"As I reflect now, I am focused on all of the many friendships and the camaraderie that have been forged along the way. 

"To all of my coaches and team-mates – I have nothing but love for each and every one of you." 

Wheelchair Basketball Canada executive director Wendy Gittens said it was a "very sad day for Canadian wheelchair basketball."

"We regret that after a long and distinguished career with the Canadian men's national team, four-time Paralympian and two-time Paralympic gold medallist David Eng has been ruled ineligible to compete at Tokyo 2020 as a result of the reassessment process," she said.

"Minimal disability athletes such as David have long been eligible to compete within international rules, and have legitimately and fairly participated in the Paralympics up until this point.

"All of our athletes, including David, are our top-most priority and we will continue to stand by them throughout this difficult process.

"The uncertainty surrounding athlete eligibility for the Paralympic Games has been extremely stressful for our teams and the entire organisation over the last five months.

"While on one hand we are relieved to confirm the status of some individuals, until we receive the results for all Canadian athletes, the ongoing uncertainty will continue to weigh on us all."

Each player's case is being reviewed by an IWBF Eligibility Assessment Panel and members of the IPC Classification Committee.

"Both are working hard to come to a conclusion on the remaining cases," the IWBF said.

The second phase of the reassessment process has already begun, and features other internationally classified players.

It will be carried out in a staggered manner with the target of all players being reassessed by the end of the year.

Men's wheelchair basketball has featured at every Paralympic Games since 1960, while a women's competition made its debut eight years later.

It has grown to become one of the most popular Paralympic sports.