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LONDON, May 21 (Reuters) - One of FIFA president Sepp Blatter's favourite lines is that his organisation boasts more members than the United Nations.
The comparison may be slightly open to question as some of FIFA's 209 members are not fully independent nations and therefore not eligible to join the UN.
But it is still a good example of the overwhelming influence of the world's most popular sport.
No other sport has quite the same ability to bring entire countries to a standstill, many declaring public holidays when their national teams are involved in World Cup matches.
Blatter, overwhelming favourite to be re-elected for a fifth term at the age of 79 at FIFA's annual Congress on May 29, frequently points out that football can even transcend conflict and diplomatic standoffs.
A memorable example was when the United States met Iran in a politically charged match at the 1998 World Cup and the players exchanged flowers before kick off.
"We did more in 90 minutes than the politicians did in 20 years," said U.S. defender Jeff Agoos at the time.
Iraq overcame the conflict at home to win the Asian championship in fairytale fashion in 2007 and, back in 1967, a 48-hour truce was called in the Biafra war in Nigeria so that both sides could see Pele play in exhibition matches.
One of the reasons soccer is so successful is that it is a truly worldwide sport, with FIFA as its one single world governing body.
Even back in the 1950s, there was a rule that if a player was banned in one country, that ban would be extended elsewhere.
Apart from a short-lived Colombian experiment from 1949 to 1954, where the Colombians paid top players directly to quit their clubs and join their outlawed league, football has managed to remain largely free of breakaways which have plagued other sports.
The simplicity of the game is another reason for its popularity.
Although soccer has been reluctant to embrace technology at the top level, that also means that the game remains essentially the same wherever it is played, be it a local match on a South Pacific island or a Champions League match in a state-of-the-art European stadium.
Yet, under Blatter's watch, FIFA's credibility has taken a battering.
There has been a wave of scandals and controversy, ranging from allegations of corruption in the 2018/2022 World Cup bidding process to a row over $25,000 watches gifted to executive committee members at last year's the World Cup in Brazil.
Since 2010, eight members of FIFA's executive committee have been banned for various lengths of time for corruption, or have resigned while under investigation.
Blatter has overseen some reforms but many critics say they do not go far enough and that, even though he has never been found guilty of any wrongdoing, it would be difficult to convince people that FIFA has changed while he is still in power.
"I think it is very difficult to change the reputation of an organisation without changing the leadership," International Cycling Union president Brian Cookson, who has set about improving his scandal-mired sport's image, told a conference last week
"However even if you do change the leadership and governance and administration, it's not a given that you are going to change and improve the reputation either."
Financially stable and with a hugely successful 2014 World Cup behind it, FIFA appears on the surface to be in good shape and, with Blatter enjoying huge support in Asia, African and Latin America, able to withstand despite all the scandals.
But it, and the sport it governs, cannot afford to continue losing credibility.
There has already been talk, albeit limited, of a boycott of FIFA, something which critics fear could lead to a scenario similar to boxing which a number of world governing bodies.
The game's power and wealth are ever more concentrated in the hands of a small number of privileged European clubs and leagues, who hoard the top players while smaller clubs struggle to survive. This has led to concerns that soccer could follow the way of basketball, where a single domestic league dominates the sport.
"If we continue along this track, it will be the capacity of FIFA to govern football which will be at stake," said Jerome Champagne, a former advisor to Blatter who was squeezed out of the presidential race by what he described as political manoeuvring.
"We need a strong governance. If we want to prevent football by being managed only by private interest, and if we want to correct the current imbalances, we need FIFA and we need a strong one." (Writing by Brian Homewood in Berne; editing by Justin Palmer)