Eto'o, 31, has been embroiled in a number of public disputes with the Cameroonian Football Federation over the past year, with relations between the Anzhi Makhachkala player and the country's governing body turning sour.
In January, the former Barcelona and Inter Milan striker - widely regarded as one of the greatest African footballers of all time - was banned for eight months for his role in organising a players' strike in a row over late payment of appearance fees.
But on Friday he wrote on his website that he would make a return, saying: "On the request of the highest authority of the Republic, I make myself available to the Indomitable Lions.
"I am encouraged by my desire to serve my country with the same faith, ardour and determination of 15 years ago.
"I was received these past days by the state authorities to discuss the present situation of football in Cameroon and specifically the national team.
"I am convinced that together, putting aside other interests for the country, we are capable, with God's assistance, of giving Cameroon football the panache, and shine of old.''
In a scathing resignation letter, Eto'o had written that the national team "continues to dwell in an environment characterised by amateurism and poor organisation not compatible with professional sports".
With Cameroon in danger of missing out on African Nations Cup qualification for the second tournament in a row - for what would be the first time since 1980 - Prime Minister Philemon Yang urged Eto'o to return for the crunch second leg against Cape Verde next month.
Cameroon lost the first leg of their African Nations Cup qualifying play-off 2-0 Cape Verde and must overturn the deficit in Yaounde on October 13 if they are to reach January's tournament, which will be held in South Africa.
Cameroon coach Jean Paul Akono told Super Sport: "The head of state has taken the situation personally and has given us instructions. We then met in a working session to pave the way forward, and all is fine."