Kuku served under former President Goodluck Jonathan.
A letter from the EFCC directed him to appear before a team of interrogators on July 28, 2015.
The letter reads: “The Commission is conducting an inquiry into a case of conspiracy, stealing, diversion of public funds and abuse of office involving you.
“In view of the above, you are kindly requested to be interviewed by the Undersigned through CHRIS OWOBU on Tuesday 28th July 2015 at No. 5 Block C Fomella Street, off Adetokunbo Ademola Crescent Wuse 11 Abuja at 10 am.
“Kindly accept the assurances of the Executive Chairman’s best wishes and highest regards, please.”
In a response through his lawyer, Tunyan Karina (SAN), Kuku said he would not be available for questioning until September 2015 as he had travelled to the United States for knee surgery.
The letter reads: “Our client is currently in the United States of America to keep appointment with his doctors at the Andrew Sports, Medicine and Orthopedic Centre, LLC, for surgery on one of his knees.
“He is expected back in Nigeria at the end of September, 2015 after the surgery and recuperation. He will definitely report in your office as a law-abiding citizen by 10am on 30th of September, 2015.”
Kuku was in May conferred with the Honorary Citizenship of the State of Georgia, U.S.A. as well as a Commendation Award by the Black Caucus of the state’s legislature.