The corruption trial of former Zambian president Rupiah Banda was thrown into disarray Tuesday when the state's star witness denied the embattled ex-leader's had benefitted from a $2.5 million oil contract.
Banda is charged with abusing his authority in awarding the Nigerian oil contract and was allegedly to benefit from the proceeds from the deal.
But the head of the firm which facilitated the deal unexpectedly denied the charges in court, and denounced the trial as politically motivated.
"Zambia never paid a single cent and it never lost any money. We paid the $2.5 million as deposit on behalf of Zambia and this money has been recovered by ourselves," said Akan Ekpene.
Having travelled from Nigeria for the trial, Ekpene broke down when a Banda lawyer accused him of turning state witness out of hate.
"I have no hatred against his excellency president Banda and if he had won the elections, I would not have been standing here and he would not have been where he is now," Ekpene said before bursting in tears and prompting a short recess.
Banda has pleaded not guilty after he was stripped of presidential immunity and arrested in March.
The trial has dragged on since April.
The 76-year-old, who led the southern African nation from 2008 to 2011, has been blocked from leaving the country three times since then.
He faces a maximum of five years in prison if convicted.
Since ousting Banda in 2011 elections President Michael Sata has cracked down on what it terms the previous government's corruption.
But critics have accused the new administration of persecuting its opponents.
Several other corruption trials against Banda are pending.