Kirk's unsuccessful attempt in 2263 to broker peace between the Teenaxi and the Fibonan Republic by presenting part of an ancient weapon as a gift.
The mission is the opening scene of Star Trek Beyond. Three years into the Enterprise's five-year mission, Kirk appears before the Teenaxi delegation as a neutral envoy. On behalf of the Fibonan Republic he offers a piece of an ancient weapon as a token of peace.
The Teenaxi are suspicious. They ask why the Fibonans no longer want it and decide that the gift is stolen or an insult. The delegates, who turn out to be creatures the size of small dogs, swarm over Kirk, and he is beamed out with one still clinging to him.
The artefact is logged in the ship's archive. It is in fact part of the Abronath, the bioweapon Krall is seeking, and its presence aboard is why he attacks the Enterprise at Altamid.