The future of football in Nigeria will be compromised if the government fails to rescind a self-imposed ban on the country's teams, the ruling body FIFA said.
A letter dated July 2 and signed by FIFA secretary-general Jerome Valcke stated the consequences for football in Nigeria should the government doesn't back down on its withdrawal of all teams from international competitions for the next two years.
"We would like to underline the dire effects a suspension could have on the future of Nigerian football. It would mean that no Nigerian team of any sorts (including clubs) could have any international contacts," the letter said.
"It would also mean that neither NFF nor any of its members of official could benefit from any development programme, course or training from FIFA or CAF any longer.
"We consider that this governmental decision would only completely isolate Nigerian football and could thus stall reforms and further development and improvement of Nigerian football for a long time.
"It puts the whole future of Nigerian football in danger."
FIFA warned that if this directive by the government is not withdrawn before 6pm South African time Monday, their emergency committee will meet and suspend Nigeria from international football with immediate effect.
FIFA have informed Nigeria that arrangements have begun for another country to replace the country at the Under-20 World Cup, which kicks off July 13 in Germany.
The world football ruling body disclosed they have established a case against the government for "a clear and blatant interference" in the way football is run in Nigeria. They said this violates FIFA statutes.
FIFA also said that elections to the NFF board slated for August 21 in Lagos must proceed accordingly and be guided by the NFF statutes.
NFF president Sani Lulu is seeking a new term in office next month and FIFA said they would be prompted by the present situation to extend Lulu's tenure, which runs out on August 28.
"As long as this decision is not withdrawn, FIFA will deal exclusively with the legitimate executive committee of the NFF, even it that means that its term must be extended over the 28 August, 2010, date originally fixed for the next elections," Valcke said.
Government officials have argued that the tenure of the NFF has expired and as such they have asked FIFA to allow them set up a caretaker management committee to run football in the country until new elections are conducted.
Former internationals Augustine Okocha and Samson Siasia have been named by government on this management committee, which is to be inaugurated on Monday in Abuja.
However, FIFA have turned down this request, warning that it will not recognise the committee.
FIFA executive committee members Jack Warner and Amos Adamu are due in Nigeria to meet with the country's government on this matter.