Kyari died of coronavirus-related complications in April 2020, five years after serving as Buhari's very influential advisor.
The late 67-year-old was widely criticized by critics for exercising powers that sometimes supposedly left the president himself aside.
With the recent appointment of Ibrahim Agboola Gambari as a substitute for Kyari, media reports claimed that decisions made in Kyari's last days were being reviewed by Buhari.
Abba Kyari died last month after losing his battle against the coronavirus disease that has infected more than 5.5 million people worldwide [Bayo Omoboriowo]
However, the president's press officer, Garba Shehu, described the reports as "fake news" in a statement released on Tuesday, May 26, 2020.
"There is not a minimum of truth in these reports and Nigerians should ignore the insinuations behind them." Shehu said.
The statement emphasized that President Buhari, 77, will never give up control of the power and trust that Nigerians entrust to him in the polls.