Aliyu also said Jonathan shouldn't have sort a re-election, adding that if the PDP fielded a young candidate from the north, Buhari wouldn't have a chance.
A former Niger state governor, Babangida Aliyu, has corroborated former president Goodluck Jonathan's story that the US plotted his removal from office.
Jonathan had fingered former US president Barack Obama as one of the forces behind his defeat in the 2015 presidential election.
He said Obama made it clear that he wanted a new government in Nigeria.
It was learnt that the Obama administration was not satisfied with the way Jonathan handled the fight against corruption and the Boko Haram insurgency.
Jonathan alleged that the former US president was so desperate that he turned world leaders against him.
He said Obama also sent warships into the Gulf of Guinea in the days preceding the election.
In a yet-to-be-launched book titled, 'Against the Run of Play', written by Segun Adeniyi, a renowned journalist, Aliyu gave a relevant account.
He said the Obama administration invited 12 northern governors to the US to discuss the Boko Haram insurgency in Nigeria.
But Aliyu said the reason for the invitation was deeper than that.
According to him, he believed that they were invited to ascertain their level of commitment to removing Jonathan.
"I have no proof of course, but I think the idea was to ascertain what the disposition of the north would be to the idea of another term for President Jonathan," he said.
"That was my reading of the situation. I believe it was all about the 2015 election for which the Americans had resolved not to support Jonathan. They just wanted to size us up for the level of commitment to regime change."
Aliyu said former Adamawa state governor, Murtala Nyako, gave the US the idea that the north was not behind Jonathan.
He said Nyako's accusation that Jonathan was sponsoring Boko Haram to destroy the north gave the Americans the signal.
"If Jonathan had been clever enough to say he would not run and had stuck with the PDP zoning formula by supporting a young northern candidate, I am most certain Buhari would have shelved his ambition to contest in 2015, knowing there was no way he would win," he said.
The book, which chronicled the loss of Jonathan in the 2015 election, will be launched on Friday, April 28.