Ben Murray-Bruce, a former Senator, says he spoke to Ismaila Isa Funtua three hours before news of his death broke.
Funtua, an aide to President Muhammadu Buhari, died late on Monday.
The president had said his death would create a huge gap, recalling how he stood by him through his “political journey”.
In a tweet, Murray-Bruce said the deceased had promised to call him the next day.
“I am saddened by the death of my brother and senior colleague, Mallam Isa Funtua. I spoke to him just three hours before his reported death, and he promised to further call me tomorrow. I pray that God comforts his family and loved ones, and may his soul Rest In Peace,” Murray-Bruce tweeted.
Funtua will be buried in Abuja on Tuesday.
The lifetime patron of the Newspaper Owners Association of Nigeria(NOAN) was from Katsina, as was the President.
He served as Minister of water resources under former President Shehu Shagari, who led Nigeria from 1979 to 1983.