In a rejuvenating overhaul, Paris 2024 announced in February that it would include breakdancing, climbing, surfing and skateboarding, subject to approval by the IOC at a meeting at Lausanne March 26-28. A final decision will be delivered in December.
There should be 28 sports with 319 events on the 2024 list, with the four candidate sports yet to be rubber stamped.
Karate officials, whose sport has been included on the 2020 Tokyo roster, were in Paris this week to try and persuade a change of heart. Squash partisans are also planning to continue their campaign for inclusion.
However Kit McConnell, head of sports at IOC, told AFP on Friday it was too late for additional candidates.
"Once the original proposal is made, it's over," the New Zealander McConnell told AFP.
"The process was clear: we have explained that the IOC could not add any more sports," he said.
"But we can cut one of the sports," he said.
"The proposal will be discussed during the meeting of the executive commission," he said
"And if the session approves the recommendation, these sports will be provisionally approved. The final decision will be made in December 2020."