Pakistan's Gulalai Ismail's visa application was made after mid-April, but she has not had confirmation it has been granted, and two Immigration offices had given contradictory answers about its status.

A prominent international human rights activist has no idea if she'll be able to attend an international conference in Auckland following lengthy delays with her visa.

Critics say Immigration New Zealand's slow response to keynote speaker Gulalai Ismail's application is shocking and embarrassing.

The International Humanist and Ethical Union (IHEU) is meeting in Auckland in early August to discuss projects and policy. It campaigns against human rights abuses, particularly from religious influences, and has representatives at the European Union and United Nations.

Gulalai Ismail from Pakistan has been campaigning since she was 14 for girls' rights to education and women's rights. She has faced death threats and been attacked more than once, but continued her work from outside the country, Humanist Society of NZ president Sara Passmore said.

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Ismail's visa application was made after mid-April, but has not had confirmation it has been granted, and two Immigration offices had given contradictory answers about its status. Another board member had been denied entry, one was still awaiting an answer, and another was initially denied and only granted a visa after a lawyer interceded.

All four do work to make their countries and the world a better place, and were all "heroes" in their own right. The response from Immigration NZ was a shock, and "embarrassing for New Zealand", she said.

The complaints come on the heels of controversy over the granting of visas for two speakers from Canada known for their extremist political stances, who were scheduled to speak in Auckland.

SUPPLIED Leo Igwe speaking at the International Humanist award ceremony in Oxford, United Kingdom, in 2014. His visa to come to New Zealand was initially denied.

The Humanist Society of New Zealand will host the international assembly and has planned its own conference alongside, so union members can take part and be speakers.

A woman who campaigns for sex education in Uganda was denied entry because Immigration NZ deemed her at risk of overstaying, and a man who is part of a group starting schools in Uganda is still waiting to find out if he will be granted entry, months after applying. The idea the members would overstay here, when they were heavily invested in projects overseas was laughable, Passmore said.

Nigerian Leo Igwe​ just finished a PhD in Germany, and arrived in the country this week. He said he was not given a reason his visa was declined initially, but after doing extensive international travel it was a surprise, and he believes it is likely because he holds a passport from a poor country.

"One of the major issues the world is facing today is religious extremism, and no other organisation I know has a mission that can help the entire world tackle this issue," he said.

"I'm surprised that New Zealand has a policy that would be applied this way. Countries like New Zealand should not undermine the goals and mission of IHEU which is for the good of the world, by making it difficult for humanists from throughout the world to attend."

Formal sponsorship for all four visitors was offered by the Kiwi humanist movement, they had sent letters of support and had a New Zealand lawyer check the applications were made correctly with all supporting documents before they were sent.

A different country is chosen for every assembly, and international chief executive of the union Gary McLelland had expressed frustration at the difficulty coming to New Zealand, Passmore said.

"He said the barriers put up in New Zealand have been very the most challenging they've gone through.

"The whole time they've been running the general assemblies no speaker or delegate has ever used it as an opportunity to illegally immigrate or overstay - it's an organisation that does this every year."

MAARTEN HOLL/STUFF Humanist Society of NZ president Sara Passmore is shocked international speakers have not been allowed into the country.

Considering New Zealand markets itself as a destination for international conferences, the process had been embarrassing, and a waste of time, union campaigns director Bob Churchill said.

"For some of those applying this is a rare opportunity to meet and talk in solidarity... in particular those from countries where simply being non-religious is regarded as a social affront and they are marginalised.

"Holding this conference in New Zealand we hoped this would offer a temporary sanctuary in a tolerant country."

Passmore said they were now worried they would loose the keynote speaker, and it was notable visitors from America and Europe do not face the same obstacles to come to New Zealand as from poorer countries.

"I want to say it's bureaucracy that's probably the main cause of it, but it's policy, bureaucracy, and a lack of transparency that made this hard. Without the lawyer we wouldn't be able to challenge any of it."

An Immigration NZ spokeswoman said they would be unable to comment during the weekend.

The conference will be held in Auckland from August 3 to 4, with the assembly on Sunday August 5.