"That's my CV. It is not that I am deliberately trying to cover-up. It's because the system asked me to use the partner university. That is the reason," Yang said.
"When I left China I was told, basically, 'use your partnership university'. And I did that. And ever since then, I stick with my partner university...China in those years was closed.
"It was over 20 years ago...they asked the military - people working in the military or studying in the military - when they leave China [to] use your partnership university. So that's what we did."
Making a false declaration is both a serious legal and political matter. Metiria Turei resigned as Greens co-leader after revelations including that she made a false electoral declaration in the 1990s.
The Herald asked Yang about his citizenship application after he held a press conference yesterday. A spokesman for National Party leader Bill English said Yang had been transparent about his association with the Chinese military system.
"We are now nine days out from an election and the Prime Minister is focused on that. If anyone has an issue they can raise it with the Department of Internal Affairs.
"We would expect the Department of Internal Affairs to treat Dr Yang the same as any other citizen."
Yang yesterday denounced an investigation into his past published by Newsroom as defamatory and a smear campaign. It reported the NZSIS has scrutinised Yang over three years and interviewed a person about the MP last year.
Yang said he had never spoken to the NZSIS and wasn't aware of any enquires. For the record, he said he had never been a spy and the implication he had been was defamatory.
He said he had been transparent about his past with the National Party and it was widely known in the Chinese community. Yang said the military institutions he attended taught English, and not intelligence training. He was a civilian officer in the military without ranking.
He was asked if he was aware that while working as a lecturer he was teaching English to people training to be intelligence officers, so they could monitor communications.
"If you define those cadets or students as spies, yes, then I was teaching spies. If that is the case. I don't think so [they were spies]. I just think they are collecting information through communication in China. If you define that way, then they were spies. But for us, it was just collecting information."
Yang agreed when he was asked if his students were using the English they were learning to monitor the communications of other countries.
He moved to New Zealand in 1999 and taught international relations at the University of Auckland, after attending the Australian National University in Canberra in 1994. He entered Parliament in 2011.
English told media yesterday Yang had been upfront with the National Party about his past.
"You get to know people as MPs and I think from early on I've been aware that he had military training including military intelligence," English said.
The National Party released to media a CV it said was provided by Yang to New Zealand's Embassy in China in 2012, as background for a visit. It included his time at the engineering university and language institute.
Yang was a member of Parliament's Foreign Affairs Defence and Trade committee from November 2014 until March last year. His is number 33 on the party list ahead of next week's election.