But the Sport Entertainment and Media Group denied reports ?80,000 was being sought for the release of Michael Obi, who was abducted in his native Nigeria last week.
SEM also confirmed Mikel had made himself available to for Chelsea's Premier League game with West Brom on Saturday, having also played in last weekend's season opener at Stoke after learning of his father's kidnapping.
SEM said in a statement on Thursday: "SEM advises that reports from Nigeria of an ?80,000 ransom demand for the return of John Obi Mikel's father is not true.
"We confirm that Michael Obi has been abducted and that the kidnappers have been in touch with the family and representatives of the family and that discussions for Michael's safe release have begun.
"A sizeable demand has been made but, for security reasons, we are unable to release details of the amount.
"Mikel would like to thank his family, friends, Chelsea FC and his agents for their support and, at this time, it is Mikel's intention to play for Chelsea this weekend, encouraged by his family to do so."
News that Mikel's father, who runs a transport company, had been kidknapped emerged on Friday after he failed to return home from work in Jos, the capital of Plateau State in central Nigeria.
Mikel appealed for information on his whereabouts on Monday and the family were then contacted by the kidnappers.
Mikel's brother Ebele Obi said in quotes reported on www.supersport.com: "Some people called my mum informing her that they have her husband in custody.
"My mum, while crying, pleaded with the abductors to release her husband."
Tony Obi, eldest son of Michael Obi, confirmed their father's car had also been retrieved.
"We got two calls from the abductors who confirmed that our father is in their custody," he said.
"They told me where to locate my dad's car, which has been found."
In a direct appeal to the kidnappers, Mikel said on Monday: "Please just let him go.
"He's just an old man, he hasn't done any harm to anyone as far as I know and I don't know why he has been taken."
Mikel, 24, is not the first Premier League player to have a family member abducted in Nigeria.
In July 2008, the elder brother of Everton defender Joseph Yobo was kidnapped in Port Harcourt.
Nornu Yobo was released after 10 days but it was never made clear whether a ransom was paid.
Source: Team Talk
Source: Team Talk