The UEFA executive committee said it needed more time to weigh proposals by the Spanish and Italian leagues and talk more with fan groups.
Fans overwhelmingly oppose taking competitive games outside Europe which soccer's world body FIFA previously blocked.
Spain's La Liga wants to stage Villarreal's "home" game against Barcelona in Miami on December 20 while Serie A is hopeful of staging the AC Milan-Como game in February in the Australian city of Perth.
UEFA said its executive committee which is meeting in Tirana, Albania, acknowledged "an important and growing issue" and wanted "to ensure that it has the views of all stakeholders before coming to a final decision."
The plans have been fiercely opposed by more than 500 fan groups in the Football Supporters Europe network that is officially recognised by UEFA.
Fans object to clubs being taken out of their home community and upsetting the balance of sporting integrity in leagues.
"We welcome UEFA's commitment to meaningful consultation," the FSE said in a statement, praising the "dedication to preserving the integrity of European football."
In Brussels, the European Commission's top official for sports, Glenn Micallef, has called the proposed game in Miami a betrayal.
There are no similar proposals from the leagues in England and Germany which would face a stronger backlash by fans than in Spain or Italy.
La Liga and Serie A have been financially outmuscled by the English Premier League's global popularity and see a chance to build the fan base and brand for clubs and leagues, following the example of US professional sports leagues.
La Liga and its commercial partner Relevent, a US marketing agency co-founded by Miami Dolphins owner Stephen Ross, first tried in 2018 to put a Barcelona game in the city but were blocked by a FIFA veto.
