Grand Slam Track will not take place in 2026 unless athletes receive their prize money for this year, says founder Michael Johnson.
Johnson said they had been “unable to meet” their timelines for payments after failing to receive funding “committed” to them, but remains “confident” about the “long-term sustainability” of the competition.
“We promised that athletes would be fairly and quickly compensated. Yet, here we are struggling with our ability to compensate them,” Johnson said in a statement on Friday.
The final event in the inaugural GST season was cancelled in June because of economic concerns.
Four-time Olympic champion Johnson said they are “putting systems and partnerships in place to make sure it never happens again”.
He said the situation is “one of the most difficult challenges” he has experienced.
The competition featured a host of well-known athletes, including British Olympic sprinters Daryll Neita and Matthew Hudson-Smith, and 1500m world champion Josh Kerr.
It offered significant financial incentives, with up to $100,000 (£73,600) on offer for winners of race categories, as well as salaries for contracted athletes.