Former United States men's national team manager Jurgen Klinsmann called the CONCACAF Nations League "a waste of time" and said that if the U.S., Mexico and Costa Rica are ever going to get to the level of the top international sides, they need to find competition outside the region.

Speaking to ESPN's Herculez Gomez in the wake of ESPN securing the U.S. broadcast rights to the Bundesliga, Klinsmann was blunt in his assessment of the CONCACAF region.

"I think the biggest challenge for the United States, or even Mexico or Costa Rica, for the key countries in this region, is you don't really have the highest competition outside," Klinsmann said. "That means when you play just within your own system, you don't have the big matches against European countries or South American countries in order to grow your program, in order to grow your players.

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"So literally when you are kind of locked into CONCACAF and you don't play Argentina, Brazil, Colombia and Chile every year, or you don't play Holland, Germany, England, Spain, Italy every year, you have no chance to grow.

"And that's what I always said, you have to leave this region here in order to make your program better, to improve your players. And this a big, big handicap for all the players and all the programs, if it's Mexico, Costa Rica or the United States."

The U.S. has played nine of the 10 CONMEBOL nations as well as England, France and Italy, since the start of 2018 -- the team also played 15 games away to European nations during Klinsmann's five years in charge -- but the advent of the CONCACAF Nations League limits the number of friendly games.

The two remaining international fixture windows for 2019 will be taken up by Nations League matches, with the U.S. in a group with Cuba and Canada. With the finals of the CONCACAF Nations League slated for next June, that only leaves the March 2020 window to schedule matches against teams from outside the region.

"It's a waste of time, I'm telling you," Klinsmann said of the new competition. "It's a waste of time because you that need [that competition] as a country. I mean talking about Mexico, everyone is hoping for the fifth game in the World Cup. You're not reaching that fifth game in the World Cup if you play the teams you are playing now in the Nations League in CONCACAF. You are not.

"Because you need to play Argentina, Brazil, Germany, Holland and England. That is your competition. And when you have an opening for a national team window and you can maybe make one or two friendly games, you need to play Argentina or Germany and not a CONCACAF team.

"So within that system that was created here, it's almost impossible for United States or Mexico to get better. And that is why Mexico just lost against Argentina 4-0."

There was always a question of how much countries like Mexico, Costa Rica and the U.S. would get out of the Nations League, given how it limits opportunities to play nations from other confederations.

But given the advent of a similar competition in Europe called the UEFA Nations League, as well as the fact that World Cup qualifying for South America will begin shortly after the 2018 World Cup concludes, those opportunities were already going to be limited.

"There will still be space for [intercontinental friendlies]," CONCACAF said in a statement accompanying the announcement of the competition in November 2017. "In broader terms, the League of Nations aligns CONCACAF with the general movement in the world of international football, away from low-stakes friendly matches."

Klinsmann added that another problem in the U.S. is that the federation prioritizes finances over results in terms of finding international opponents.

"There might not be the financial benefit to it when you travel to Italy or to Holland or to Germany or to England, than playing a home game in the United States with the, I don't know, whatever revenues are coming in," he said. "So at the end of the day it is very, very difficult to make your players better when they don't have the highest competition possible."

When approached by ESPN, U.S. Soccer declined to comment.

In the interim, the priority for U.S. players is to seek out the high-level club opportunities, in particular playing for European teams.

"The players need to play in the best leagues in the world, which are in Europe, as many as possible," Klinsmann said. "Which we are very proud of, a lot of them now playing in the Bundesliga, or Christian Pulisic playing in the Premier League. This is super exciting.

"And the same with the Mexican best players, they play in Europe, it doesn't matter where they play. [Hirving] Lozano plays in Napoli and [Javier Hernandez] plays [with Sevilla], and so on. So the challenge for a coach is always, 'How do I get my players to play at the highest level possible for them?' And if not, then you know you always have these setbacks."

Klinsmann also insisted that he thinks MLS benefits American players, just that some things can be improved.

"I think MLS is a wonderful place, to come through, to fight through," he said. "I think that the coaches here that really try to give the younger players the chance, I see a lot of young players now out there. And then it's down to the players as well.

"So how far do I want to take it now from here? I think with the growing MLS, every year the quality is improving. Every year they are trying to compete more, especially with Liga MX, which is awesome to do. I think the developmental path is there. But they have got to give a clear message to the players as well that it is down to them to become more consistent."