Mikel Obi has returned to training, but will miss this week's first squad meeting with Technical Adviser Lars Lagerback as well as the Presidential Dinner in Abuja.
The midfielder has started light running but is continuing his rehabilitation from knee meniscus surgery. Nigeria President Goodluck Jonathan is expected to send off the team at a dinner in Abuja on May 20.
The day before the dinner, Lagerback will meet up with his squad for the first time since being appointed in March but Mikel's representative John Shittu told KickOffNigeria.com that the Chelsea midfielder would be unable to make the gathering
"He has started running and is training again but he is still undergoing rehab after his surgery and he will be unable to come to Abuja this week," Shittu told KickOffNigeria.com.
Mikel, who told KickOffNigeria.com that he would be out for two only weeks, is making good progress after having his torn meniscus repaired.
Shittu says he will be fit to take part in Nigeria's World Cup build-up.
"Everything is going well, there are no complications and he will be available to take part in the preparations for the World Cup."
On Saturday, Mikel picked up an FA Cup winners medal with Chelsea despite missing the Final.
"I just got my medal in the dressing-room," he told KickOffNigeria.com after picking up the prize piece of silverware.
Nigeria play Saudi Arabia, Colombia and North Korea before their opening game on June 12 against Argentina.
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