Oluwashina Okeleji BBC Sport, Lagos

Mikel has played four times for Nigeria

The Nigeria Football Association (NFA) has ordered Chelsea to release Mikel Jon Obi for next Saturday's Nations Cup qualifier against Uganda.

Chelsea have written to the NFA telling them Obi is undergoing treatment following a hamstring injury.

But the NFA want Obi to be assessed by their team of doctors.

"The NFA is not satisfied with the club declaration hence we expect Mikel to be in Uganda for the game," NFA spokesman Ademola Olajire told BBC Sport.

Olajire added: ""If our medical team confirm that he's not fit to play then will surely he'll be rested.

"We've made it clear that due process be followed and the said player be released immediately according to Fifa rules."

The Nigerian camp has been ravaged by injury as midfielders Yusuf Atanda Ayila and Seyi Olofinjana have been ruled out due to injury.

Meanwhile, Nigeria coach Berti Vogts has ordered Obafemi Martins to report to the team's camp in Kenya or forget about playing for the national team in the future.

The Newcastle striker failed to join the rest of the squad in Kenya as expected over the weekend, claiming that he is injured.

But his absence has drawn the ire of the German coach, who has ordered the striker to join the team before they depart Kenya on Thursday.

"Instead of joining the team here he travelled to Nigeria which is very disappointing," Vogts said.

"This camp was organised mainly for the England based players as their league ended three weeks ago.