on the sidelines

Idioms  

1. Observing rather than taking part, out of the action, as in Bolivia's neighbors remained on the sidelines, waiting to see which faction in the dispute would prevail. This idiom comes from sports. The sidelines are the two lines defining the sides of the court or playing field and the area immediately beyond them where, in such sports as football, the non-playing team members sit. [First half of 1900s]

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Example Sentences

Officials from Britain, France, Germany and Italy were present in Geneva and held talks with the Ukrainians on the sidelines of the trilateral meeting.

From BBC

Rivals OpenAI, Google and xAI have agreed in principle to have their models deployed in any lawful use cases, a Pentagon priority, Emil Michael, the undersecretary of war for research and engineering, said in an interview on the sidelines of a defense summit in West Palm Beach, Fla., on Tuesday.

From The Wall Street Journal

“While the majority of builders continue to deploy buyer incentives, including price cuts, many prospective buyers remain on the sidelines.”

From The Wall Street Journal

Over the weekend, the US and Japan affirmed their ties on the sidelines of the Munich Security Conference in a meeting between US Secretary of State Marco Rubio and his Japanese counterpart Toshimitsu Motegi.

From BBC

"I think it risks looking like a truce, and we don't know how long this truce will last. We have seen many ceasefires in the Democratic Republic of Congo that have not lasted long," Mukwege told AFP in an interview on the sidelines of the Munich security conference.

From Barron's