Mwamba, popularly known as GBM has also apologized to President Edgar Lungu for having uttered disparaging remarks against him.
During a media briefing at his office in Villa Elizabeth, Mwamba said that Hichilema repeatedly undermined him as his deputy and opted to work with his inner circle.
He said that Hichilema was an arrogant person who did not heed to advice.
Mwamba said Hichilema had rendered his deputy presidents irrelevant hence the turnover of vice presidents was too high.
He said that losing five vice presidents showed that Hichilema was an intolerant person.
“They should abolish the position of vice president because it is irrelevant. No wonder they have lost five vice presidents. My brother always side-lines his vice presidents and deals with a kitchen cabinet,” Mwamba said.
Mwamba said that he was always reaching out to Hichilema before matters completely got out of hand.
He said that they held meetings aimed at clarifying their deteriorating relationship but Hichilema never kept his side of the bargain.
He also apologized to president Lungu for having insulted him before defecting from the PF in 2016.
“I will be failing if I do not publicly apologize to President Lungu for all the disparaging remarks and insults I showered on. I publicly apologize to him,” he said.
In re-joining the PF Mwamba said he had followed the majority of his supporters’ wish and not form an own political party.
Mwamba said that the UPND had opted to disrespect him after having helped them build structures in Northern Province.
He said Hichilema was using some weak elements from Northern Province like Patrick Mucheleka, Mutale Nalumango and Bernard Mpundu to maintain a presence in Northern Province.
Mwamba said he had forgiven all the UPND officials that voted to suspend him after the National Management Committee.
He said that as vice president, he was never allowed to interact with MPs freely as they were directly under Hichilema.
“Even in PF the vice president Inonge Wina is in charge of Ministers but in the UPND it’s the president and the Secretary General, I have forgiven HH because he is being cheated by his litigants and my relative Muchekeka “, he said.
He becomes the sixth UPND vice president to resign since Hichilema took over in 2006.
The list includes Sakwiba Sikota, Bob Sichinga, Francis Simenda, Patrick Chisanga and Dr Canisius Banda.