Earlier this year, the teams agreed to allow blanket-free full wets from the Emilia Romagna GP onwards.
After the Imola event was cancelled, the tyres were used for the first time by three drivers in the Monaco race and were then tried by the whole field in FP3 in Canada.
As Pirelli works towards the possible introduction of blanket-free slicks for 2024, the company wanted to fast-track its new intermediates into race weekend use within this season.
The Singapore GP was earmarked as the potential starting point given production and transport schedules. At least eight teams had to support the decision.
However, despite promising feedback from testing, in a vote taken during the Monaco GP weekend, a majority opted not to make the change.
"Usually we have some races with rain, like Suzuka, for example," Isola told Autosport. "And it was a good opportunity to test them before the end of the season.
"The problem is that to test them as an additional prototype is difficult because we should send them everywhere in the world.
"I was talking to the FIA, offering the intermediate for Singapore, and then they came back to me saying no.
"The teams didn't agree. Unfortunately, we had more than two teams against, because we needed eight teams in favour."
Source: Autosport