Max Verstappen is getting involved in Honda's plans for the future.
It has emerged that Red Bull's works engine partner is currently not willing to commit to Formula 1 until it sees the highly controversial new 2021 rules.
Amid that, Dutchman Verstappen recently got involved at the highest levels of those deliberations.
"He wanted us to explain the plan we have. We did that for Max and his response was that Honda has so far fulfilled what we promised.
"He maintains his confidence in us," Yamamoto added.
Next year, a sell-out crowd of Verstappen's countrymen will descend on Zandvoort for the first Dutch GP in decades.
Dutch GP boss Jan Lammers told RacingNews365 that he hopes Red Bull and Honda collaborate even more deeply in future.
"I hope Honda will take over Red Bull completely," he admitted.
"Toro Rosso is already changing its name next year, and let's not forget that Red Bull is strongly influenced by the Thais. It is probably no coincidence that Alex Albon is currently in that car."
For his part, Honda technical director Toyoharu Tanabe says he is happy with Red Bull.
"I was not involved in the McLaren project, but Red Bull and Toro Rosso are very open as a team and the engineers are very open minded," he told the Dutch publication Formule 1. "We are very happy here."