The Irish Football Association has vowed to prevent any repeat of an incident which saw a firework thrown on to the pitch at Windsor Park after receiving a warning from disciplinary chiefs.
UEFA's control, ethics and disciplinary body launched an investigation after an object was thrown on to the playing surface from a section housing visiting supporters during Northern Ireland's 0-0 Euro 2016 Group F qualifier draw with Romania on June 13.
IFA chief executive Patrick Nelson said: "The Irish FA is satisfied with this decision. It proves Northern Ireland fans were not responsible for the incident, and it upholds the good reputation of our fans.
"We will take heed of the warning from UEFA and endeavour to ensure such an incident is not repeated at the National Football Stadium."