The National Federation from the The Netherlands has sent a letter to the IBA, informing them that van der Vorst will be resigning from the position.

Van der Vorst is an interim Executive Board Member of World Boxing. 

"World Boxing was presented to the global sports community on April 13, where I am among the interim Executive Board members, together with leaders from GB Boxing, USA Boxing, and others," van der Vorst wrote in a letter announcing his decision. 

"World Boxing aims to save the Olympic-style boxing for the future generations by securing its place within the Olympic Family. 

"That requires an immense investment of time and attention. 

"For that reason, I have decided to step down as the President of the Dutch Boxing Federation and allow others to stay focused on driving Dutch boxing forward."

The Dutch Boxing Federation has also claimed that its General Assembly has not yet decided whether it will participate in World Boxing or allow the participation of van der Vorst in the newly formed body.     

So far, the only National Federation to officially announce that it is joining the new body, described as a "rogue organisation" by the IBA, is USA Boxing.

When it launched last month, World Boxing promised that several members would be announced in May. 

Apart from the Dutchman, World Boxing is led by an Interim Executive Board comprised of representatives from the National Federations of Germany, Britain, the Philippines, Sweden, and the United States.

Keeping "boxing at the heart of the Olympic Movement" is one of the five key pillars prioritised by World Boxing, along with putting the interests of athletes first, and delivering sporting integrity and fair competitions.

World Boxing has signed Sport Resolutions as an independent provider of arbitration and mediation services and the company will be tasked with appointing an independent vetting panel.

The new body is planning to hold its inaugural Congress in November.

Van der Vorst also leads the Common Cause Alliance (CCA), established to prioritise boxing's presence at the Olympics, which is in doubt from Los Angeles 2028 and not guaranteed for Paris 2024 due to a row over technical officials.

But CCA members Australia, France, Canada and Ireland were not present for the launch of World Boxing.

However, Ireland has said it shares the same principles of the new body. 

Lithuania also welcomed World Boxing but has not committed to joining them yet, with its President Darius Šaluga saying IOC recognition must be a priority for the new body. 

Van der Vorst continued that he is resigning as the head of the Dutch Boxing Federation with a "heavy heart" and thanked everyone for cooperating with him over the years. 

In his letter, he also indicated that current treasurer and vice-chairman Jeroen van den Berg is willing to replace him.

"Of course, I am pleased that our current treasurer and Vice Chairman, Jeroen van den Berg, is willing to replace me and would like to be elected as President at the upcoming General Assembly. 

"He certainly deserves for the dedication and good work in recent years. 

"In fact, I have full confidence in the entire current Board, including Jeroen, Ab el Ballouti, Len Huard, Roos Spanjer, John Bersch, Saskia Aben, Paul Wenting, Michel van Halderen, Jeremie Besson, and Bernard Jansen. 

"They are all carrying our important and meaningful projects for Dutch boxing." 

However, the 51-year-old added that he wished to "remain involved" with the National Federation in another role and wished boxing in the Netherlands "all the success and prosperity in the years to come."

"I hope to see you all on Monday, May 29, at the General Assembly in Eindhoven, where we will be making important decisions for the future of the Dutch Boxing Federation," he said.  

"We need all the expertise, passion and support of our united boxing family!

"I will always remain in your corner."