Immigration New Zealand wants 28-year-old Sopheng Veng deported, but his doctor says he poses a "very limited risk" and he wants to complete his course before leaving.

Mr Veng, a postgraduate accountancy student, had been given the medical clearance for a student visa in 2006 but his application for a further visa in 2009 was declined after the department found him to have an unacceptable standard of health.

Although he stopped going to classes, Mr Veng has lodged multiple appeals against the decision, which has continued to be listed as "pending" since February 26, 2009.

Immigration NZ issued him with a short-term visa this month because he did not hold a valid visa. That was so he could leave lawfully by August 7.

Hepatitis B and C can lead to liver cancer and liver failure, and Mr Veng believes he may have been passed the infection by prostitutes he visited here.

Jon Wilcox, Mr Veng's doctor, said: "The Immigration argument is that he might be an unexpected cost to the taxpayer to pay for any emergency liver treatment.

"This argument is flawed, spurious and clinically naive," he said, and besides, Mr Veng had insurance.

His health was quite satisfactory and "he is of very limited risk to anybody, except perhaps a partner".

Mr Veng is appealing to be given a chance to finish the course that would qualify him to practise as an accountant. A plea to the Immigration Minister by his doctor has been rejected.

Mr Veng said his family had spent over
$100,000 to send him to NZ.

"The least I can do is to go back with a qualification that will allow me to find a good job as an accountant in Cambodia so I can repay them.

"I have made a mistake but I have not committed a crime."