The party was reacting to media reports where Fayose castigated Buhari as not competent to contest election.
The State Publicity Secretary of the party, Taiwo Olatubosun, said the governor's action gave him away as an "unconscionable character who ought to hide his head in shame over his sundry activities that marked him out as a tragedy on the question of integrity."
According to him, Fayose is not competent to question any Nigerian over issues relating to integrity.
"Buhari told Nigerians about his educational qualification and reasons for visiting London. Except Fayose who said he saw Buhari in a London hospital, other people saw him at a private home and Chatham House where he delivered a public lecture.
"Lying is a question of integrity. A liar does not have integrity. Lying leads to deceit, stealing, conspiracy, murder and other vices. While Buhari has never and would never be associated with any of these vices in both private and public life, same cannot be said of Fayose who goes about with chains of alleged criminalities tied around his neck.
"It is amusing that a man once convicted of lying at the Ekiti State High Court would be the one accusing the innocent of lying.
"The latest in his lies is the denial of his involvement in the criminal conspiracy with his ilks in the Ekiti poll fraud as his voice was heard on how he collected INEC soft copies he printed to fraudulently win June 21, 2014 governorship election."
Describing Fayose as a rare breed in brigandage with no sense of shame, the APC spokesman said the governor had baggage of alleged crimes on his neck from which he had not exonerated himself.
He advised Fayose to start thinking of how to plan a life after paying for his alleged crimes, noting that Buhari's presidency was a reality that could not be stopped by Fayose's frustrating tantrums.