It seems we may not see Barcelona supporters waving flags in the stands in Miami. (Albert Gea/Reuters)

In August, the Relevent sports and entertainment company announced that it had struck a 15-year deal to have La Liga, Spain’s top-flight soccer league, play at least one match every year in the United States. But the move was greeted unfavorably by just about everyone who would need to be involved.

Now FIFA has joined the opposition, announcing Friday that it will not support any league’s attempt to play games outside its own country.

“Following a request for guidance from the Spanish FA, US Soccer and CONCACAF, the FIFA Council discussed La Liga’s proposal to host an official 2018/19 regular season league match outside Spain (in Miami),” world soccer’s governing body said in a statement posted on the FIFA website. “Consistent with the opinion expressed by the Football Stakeholders Committee, the Council emphasised the sporting principle that official league matches must be played within the territory of the respective member association.”

FIFA President Gianni Infantino, speaking after the FIFA Council met in Rwanda to discuss numerous matters, drove that point home.

“Consistent here with the opinion already expressed by football stakeholders committee, the council emphasised the sporting principle that official league matches must be played within the territory of the respective member association,” he said, per the BBC. “So the council has very clear views on that.”

FIFA’s opposition was expected, though La Liga maintains that world soccer’s governing body does not have the jurisdiction or authority to block La Liga’s plan and is threatening legal action if it does so.

“Should we receive official notification from FIFA that they prohibit the match in the USA, we will take the case to the Court of Arbitration for Sport (CAS) with urgency,” La Liga said in a statement to The Post.

CAS is a quasi-judicial body based on Lausanne, Switzerland, that settles legal disputes involving international athletics through arbitration.

The Spanish soccer federation must first sign off on the deal, however, and it already has expressed an unwillingness to give its approval. Earlier this year, federation president Luis Rubiales accused La Liga President Javier Tebas of trying to “invade” the United States and said he spoke to “everyone except the people he should have” while planning the move.

The Spanish players' union also opposes the U.S.-based games.

“We have said it 200 million times, the players will not go to those games,” David Aganzo, president of the Spanish players' union, said via the BBC.

There are still a number of steps that would need to be taken before Girona and Barcelona — the two Catalan teams tabbed to play in the United States this season — take the pitch in Miami on Jan. 26. If the Spanish soccer federation gives its approval, it would then trigger a request for approval to UEFA, the governing body of European soccer. If UEFA approves, then the U.S. Soccer Federation and Concacaf — the governing body of soccer in the North and Central America — must also give the go-ahead.

Relevent — which owned by Stephen Ross, who also owns the NFL’s Miami Dolphins — has for years staged a summer preseason tournament in the United States featuring some of the world’s most popular European teams under the International Champions Cup banner. The agreement with La Liga was reached to build the Spanish’s league’s presence via regular season games in America, where the English Premier League attracts the majority of attention in terms of international club play.

“Our goal, our job, our responsibility is to try to build La Liga,” Relevent executive chairman Charlie Stillitano told The Post’s Steven Goff in August. “We told them, [Relevent] sees the power of regular season games.”

The NFL for years has staged games in London and Mexico, and Major League Baseball will stage a two-game regular season series between the Yankees and Red Sox in London next year. But Spanish clubs were loathe to give up a lucrative home game, especially matches involving fan-drawing powers Barcleona, Real Madrid and Atletico Madrid.

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