To boost the relationship between F1 technology and road cars, tyre size grew from 26.4 inches (13-inch wheel rims) to 28.3 inches (18-inch rims) for the arrival of ground effect in 2022.
This followed the 2017 move to 'wide cars', which marked the introduction of a 2.4-inch wider front tyre and a 3.15-inch growth for the rears compared to the previous 2010-16 generation.
However, the bigger rubber contributes to a new minimum car weight limit of 798kg. This bulk led to driver complaints that the machinery is lazy and understeers. In turn, the slow-speed handling has partly offset the desired overtaking gains brought by the regulatory overhaul.
As such, Pirelli - which signed an F1 contract extension to exclusively supply tyres until 2027, with an option for a further season - is anticipating a design brief to return to smaller rubber.
Pirelli motorsport boss Mario Isola told select media, including Autosport: "[In] 2026, we have a completely new car, probably a new tyre size.
"[Smaller, lighter tyres], it's possible. It's not defined yet, but the target is not a secret: that is to design lighter cars, more agile cars and tyres are a part of the weight of the car.
"So, it can be that we have to supply smaller tyres. If we have to supply smaller tyres as we did in the past, we will change again in 2026.
"It's part of our agreement with Formula 1 to follow the request of the stakeholders to design a tyre that is always in line with the target defined by all the stakeholders."
Isola added that reducing tyre size was the primary way of meaningfully making the rubber lighter given the current construction already leans heavily on weight-saving technology.
He explained: "The elements in the construction, we are already using materials that are high technology materials that are very light.
"If you put a lot of weight into the tyre, you generate more heat. Generating more heat means that the risk is to blister or create other situations that are not good for the performance and durability of the tyre.
"When we decided to produce the new construction in Silverstone [earlier this year], it is just a new material that is, with the same weight, more resistant.
"So, our research and development on new materials - we have a dedicated department for reinforced materials and compounds - are always looking at improving the resistance of the material, keeping the weight as low as possible.
"That's useful also for the technology transfer [to road cars]."
Pirelli has also revealed that it is imminently about to begin analysis into the 2025 F1 tyre construction amid growing driver complaints about the high levels of degradation.