BERLIN, June 13 (Xinhua) -- Former German national team coach Juergen Klinsmann is convinced that "Brazil and Argentina are extremely hungry" for success in the 2018 World Cup in a recent interview with Xinhua.

If Germany were to retain the World Cup it would be an "incredible achievement", added the former Bayern Munich and Tottenham Hotspur striker.

The 53-year-old said there was little to choose between the top nations and the "details will decide in 2018".

The 1990 World Cup winner and 1996 European champion said that France and Spain are "exceptionally skillful and will be extremely hard to beat."

German fans shouldn't see their team as the only favorite. "If they (Germany) do manage to successfully defend their title we will have to give them all the medals for bravery we can find. It would be massive," said he.

"(German national team coach) Joachim Loew's players know all about expectations and the burden of being the team everybody wants to beat."

To Klinsmann, developing a similar ambition and hunger is the biggest problem for a World Cup-winning team.

"It's not easy as I remember from 1994. We won the 1990 World Cup and failed four years later because we couldn't develop the same determination in the tournament," said Klinsmann, who was Germany's head coach from 2004 to 2006.

Loew was his assistant coach when hosts Germany finished third in 2006. Other teams can rely on more individual quality, but the most significant German advantage is "their unbreakable team spirit", Klinsmann said.

"The team can always invest a little bit more in the dying minutes while others seem to run out of energy," he said.

"The French squad has more individual quality and talent than most others but that is not always the key to success.

"What is important at a tournament is the atmosphere, the hierarchy and the ranking in the squad. You need to be a real team dying for each other," the former United States national team coach said.

Germany's advantage is Loew's unique ability to get everyone to toe the line. Klinsmann called Loew the ideal coach that works strategically and with care. It is important to be empathic to guide young talents to a world-class level. "He has the gift to do that, and he is taking the right steps at the right time."

Klinsmann is convinced Loew's decision to extend his contract until 2022 could influence the performance of the German team at the World Cup. The US-based former player felt it would ensure consistency and he considers it a big advantage for the national team.

Klinsmann said the new trend of high-speed football only makes sense "when you can keep a clean sheet".

"Today a successful team must be able to play different tactical systems; it is not just speed that leads to titles. It is the mixture of smart defending and rocket-like attacks."

Klinsmann said his experience told him that a solid base is vital for countries that are trying to develop the game.

"It's an enormous challenge for a huge country like China for instance, but without a good foundation your house won't be a solid enough," he said.

China is well advised to invest a lot of energy in youth development and in an academy system.

The right steps are being made but patience is needed to reach a higher level in world football, said Klinsmann in talking about China's promotion in soccer.

It was in the years after 2006 that German football benefited from the improvements of the advanced academy system implemented over 12 years ago.