Dr. Obinna Obeta, 51, is charged with participating in an international criminal conspiracy in a scheme to traffic organs.
The Old Bailey was informed that Dr. Obeta had travelled in 2021 with a donor from Nigeria whom he had misidentified as his cousin.
He disputes that he violated anti-slavery legislation.
Ike Ekweremadu, a former politician from Nigeria, is charged with bringing a man to the UK to donate a kidney to his daughter Sonia.
In order to take advantage of the young guy in May 2022, Mr. Ekweremadu, his wife Beatrice, 56, and daughter Sonia, 25, deny planning or facilitating the young man's visit to Britain.
Dr. Obeta is charged with participating in the scheme.
The court learned on Monday that Dr. Obeta received a kidney transplant in the UK in 2021 from a donor who travelled there from Nigeria and was reportedly his cousin.
But, when Sally Howes KC, his defence attorney, questioned Dr. Obeta, he refused to say that the man was his cousin.
"No, he's not a blood relative. I wish to apologise for that," Dr Obeta said.
"At that point I was really desperate to survive," he added.
Asked if he accepted that by identifying him as a cousin that was a lie, Dr Obeta said: "I'm not proud of that."
Dr. Obeta testified in court that he had maintained contact with the patient after the procedure but denied having given the donor any payment or other form of compensation for his kidney.
"He was more like my son at this point," Dr Obeta said.
The court was informed that following his surgery, Dr. Obeta had been in touch with his donor to inquire about the possibility of finding any other donors.
"There were others I had in mind. It's not an easy task," said Dr Obeta.
He testified before the court that he needed to understand the motivations of potential donors because some would not have the right kidneys.
Dr. Obeta allegedly sought to replicate the procedure he had successfully used with the Ekweremadu family, who required a kidney for their daughter Sonia, according to the prosecution.
The potential donor, who cannot be named for legal reasons, allegedly fled after Royal Free Hospital medical staff determined he wasn't a good candidate, according to information previously provided to the Old Bailey.
Next, it's said that Dr. Obeta sought for a another street vendor to be a potential organ donor for Sonia Ekweremadu.
An accusation under the Modern Slavery Act is refuted by all three defendants.
The trial goes on.
