TGM made the surprise announcement on Tuesday morning that Oyu will not race in the Suzuka double-header on October 27-29.
It effectively confirms the end of the Servus Japan-run team's association with Oyu after a turbulent 2023 season that has yielded two pole positions and a best race finish of third.
TGM's statement said that Oyu had made a "heartfelt request" to sit out the two final races of the season after a turbulent season in which he has finished inside the points only twice in the six races he contested.
An official comment from Oyu, which was also posted on the 25-year-old's own social media page, read: "As a new challenge, I started this season with a new team. It has been anything but easy, but I've given my all in each and every race.
"Despite my own mistakes and some times when things with the team didn't go well, I was able to work as one with the team and I received a lot of support from many quarters.
"There are still two races to go this season, but the situation I'm currently in has made it very difficult to prepare myself to race at Suzuka, or even try to win.
"After thinking carefully about the people who have been supporting me, and my own personal desire to somehow see out the season, but also about my the current harsh reality I'm facing, I came to this decision [to withdraw]."
Oyu moved to TGM this season after three seasons at Nakajima Racing, but had to raise his own funding to secure the seat after turning down a Honda offer to join Dandelion Racing.
He won at Suzuka in his rookie season in 2020 but a second victory has proven elusive, with both the races he started from pole this year at Suzuka and Sugo ending in non-finishes.
Cem Bolukbasi's team-mate at TGM for the final two races of the season has not yet been announced. Hiroki Otsu, who took over the seat at Fuji in July when Oyu was injured, has already been confirmed as Naoki Yamamoto's stand-in at Nakajima.
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