National has re-ignited the free speech debate by calling on the Government to bar ex-US army intelligence analyst Chelsea Manning from visiting the country next month.

Former Immigration Minister Michael Woodhouse said the "convicted felon" should not be allowed to earn money talking about her crimes, and it would "not enhance" New Zealand's relationship with the US.

But Green spokeswoman Golriz Ghahraman said Manning had stood up against authority and silencing her was "callous".

GETTY IMAGES National MP Michael Woodhouse said Chelsea Manning shouldn't be allowed to profit from her engagements because of her convictions.

The Free Speech Coalition labelled National's stance "foolish" while Wellington's mayor said Manning had a right to free speech and he would welcome her to his city with open arms, as long as she was allowed into the country.

READ MORE:

* Manning on life after prison, and why she isn't going away any time soon

* Freed after seven years in prison, Manning 'figuring things out'

* Minister pleased as Robert Mugabe's henchman leaves New Zealand

Manning, who was sentenced to 35 years in prison for leaking hundreds of thousands of classified American diplomatic and military documents, has two speaking events scheduled in early September.

SUPPLIED Chelsea Manning is due to speak in New Zealand in September, but needs special clearance to enter the country.

Her conviction for espionage and computer fraud means she will require a "special direction" from the Government to allow her into the country.

This can come from a senior immigration official in the first instance, and then can be appealed to Associate Immigration minister Kris Faafoi, who has the delegation for special directions.

Manning was granted a commuted sentence, not a pardon, by former US President Barack Obama, so her convictions still stand.

A spokeswoman for Faafoi said a request had not yet been received on Monday, and he would not be commenting on a decision ahead of actually making it.

Immigration New Zealand said no visa application had been received as of Monday night, but on Tuesday confirmed it had. Manning's representatives had attempted to sent an application on 16 August, but the file had been too large to be received. It has now been successfully received.

Woodhouse said if an application from Manning had landed on his desk while he was Immigration Minister, he would have denied it, and called on the Government to do the same.

RICKY WILSON/STUFF Green MP Golriz Ghahraman said Manning was holding power to account and suggesting she should be barred is ridiculous.

"This is a convicted felon, sentenced to 35 years in jail, coming in here for money," Woodhouse said.

"She is wanting to be hailed as a hero for stealing military secrets and state secrets. She was convicted of very serious crimes.

"The discretion is not there to apply to a person who expresses virtually no remorse for her offending...There's no rehabilitation, no remorse, the very purpose of her visit to come and talk about her crimes."

"The other thing to consider is that we have a very good and friendly relationship with the US, which I have no doubt would not be enhanced."

The prosecution in Manning's court martial were unable to prove that her leaks caused any harm to human life, and a recent Pentagon analysis found they had no strategic impacts on the wars in Iraq or Afghanistan. But Woodhouse said it was basically impossible to prove harm because of the nature of the crimes.

"I'm a firm believer in free speech. But I don't believe there is a basis to say that her crimes are victimless. We will never know because of the nature of her offending - whether there are people that were put in harm's way," Woodhouse said.

Green Party foreign affairs spokeswoman Golriz Ghahraman said Manning should definitely be let into New Zealand.

"She got her criminal convictions for acts that were in fact in the public interest. She doesn't pose a risk for New Zealand in relation to anything that dates back to those convictions...It's not like she was a drug or sex offender," Ghahraman said.

"She was trying to hold people to account for misuses of power. Which we welcome. She raised alert and really bravely put herself on the line. To say we are now going to stand with the oppressors that she was exposing is really offensive.

"Silencing Chelsea [Manning] is particularly callous - given she has already done her time through a lengthy term of imprisonment in particularly difficult circumstances."

Manning attempted suicide twice in prison.

Prime Minister Jacinda Ardern refused to comment on the situation on Tuesday morning, saying it was a matter for her immigration minister.

Manning is scheduled to speak in Auckland on September 8 and at Wellington's Embassy Theatre the following day.

Wellington Mayor Justin Lester said he would welcome Manning to the city with open arms if she was admitted entry into the country.

"Absolutely - for a right to free speech. If she complies with New Zealand immigration law, then she's welcome here. I'm sure there'll be lots of interest and interested observers."

Lester acknowledged not everyone might agree but they were each entitled to their own view. "In my view, if she complies with the law, then we're happy to welcome Chelsea here. I hope she enjoys Wellington."

Auckland council recently sparked legal proceedings after Auckland Mayor Phil Goff barred two controversial Canadian speakers from using a council venue. Regional Facilities Auckland cancelled right-wing Lauren Southern and Stefan Molyneux's August 3 booking of the Bruce Mason Centre, citing concerns about safety.

But Auckland council declined to comment on Manning's planned appearance as she was not booked in a council venue.

The Free Speech Coalition was formed in response to the Auckland decision. Coalition member Chris Trotter said Woodhouse should reconsider his comments.

"As a democracy, we have a right to be informed on the activities of our friends on the international stage. New Zealanders deserve a chance to hear her speak," Trotter said.

"There are other examples of previously convicted criminals that have been allowed entry into New Zealand. Nelson Mandela was allowed entrance in 1995. And Jordan Belfort, also known as the 'Wolf of Wall Street', was allowed to give a series of motivational speeches in 2014. If these convicted criminals were able to speak in New Zealand, why is Manning any different?"

"I think the National Party is very foolish to take this position because it looks like it is upholding the right of the right to speak but not of the left."