What does the US say about participating in the same exercise with China?

Beijing [China], September 11: Chinese soldiers will take part in Brazil's annual military exercises this week, which also involve US forces.
The Brazilian Navy is holding its annual exercise , Operation Formosa, this week. Last year, China was only an observer, but this year it will send full-fledged troops, according to Reuters. US troops participated in 2023.
"In Operation Formosa 2024, for the first time we will have the participation of troops from both countries," the Brazilian Navy said of the presence of the two superpowers in this year's exercise, although it did not specify the number of troops.
The Brazilian military will deploy 3,000 soldiers in the three-day exercise, which starts on September 11. Soldiers will practice using aircraft, tanks, armored and amphibious vehicles, artillery, rocket launchers and missiles.
The live-fire exercise took place outside the town of Formosa, 80 km northeast of Brazil's capital Brasilia.
Military personnel from invited countries will attend seminars to exchange experiences and eight other countries will also send observers.
Pentagon spokesman Pete Nguyen said US and Chinese forces would not train together during the exercise. He said US Marines were participating in the exercise only to train with their Brazilian counterparts.
"By working alongside our Brazilian partners, we are strengthening our collective capacity to respond to security challenges in the region," said Nguyen.
Source: Thanh Nien Newspaper