A collective of some of New Zealand's biggest brands is set to pull ads from Facebook and Google after a gunman live-streamed his massacre of 50 people at two Christchurch mosques.

The Herald understands that ASB, Lotto NZ, Burger King, Spark and number of other companies have banded together to take a stand against the harm caused by unmoderated content.

It's understood that marketing managers from the different companies spoke over the weekend about what they could do promote change in the industry.

At this stage, it is still unclear how extensive the pull-back will be or for how long the companies are likely to pull their digital ads.

Other brands have also acted independently. Kiwibank, ANZ and BNZ have suspended much of their digitial advertising since Friday afternoon after news of the attacks broke.

This is not the first time New Zealand companies have pulled ads from these platforms.

Only several weeks ago, Spark pulled all its advertising from YouTube over concerns about paedophilic content targeted at children.

Spark's move was part of an international response, which also saw Disney and Nestle pull ads from the site.

Spark corporate relations lead Andrew Pirie confirmed to the Herald today that the telco was in talks with other companies, but had not yet finalised details of the action it would take.

Several years ago, numerous Kiwi brands also pulled their money after it was revealed that their ads appeared alongside extremist content.

Lessening the flow of money into these companies is the one way in which companies can get an immediate reaction from the big tech companies – as illustrated by YouTube's decision to ban all comments on content featuring minors after brands took exception to the unsavoury remarks often made.

A joint statement today from industry bodies the Association of New Zealand Advertisers (ANZA) and the Commercial Communications Council (Comms Council) called on social media platforms to do more to ensure that such horrors are never again live-streamed.

ANZA chief executive Lindsay Mouat today told the Herald that New Zealand companies need to consider where they want their advertising money spent.

He said that in the aftermath of the Christchurch massacres, he had "a real outpouring of concern" from senior marketers asking what they could do to help change this.

Mouat said he believed New Zealand's businesses had a role to play in encouraging change.

"Perhaps when the dollars start to go, you'll get a response," he said.

While Prime Minister Jacinda Ardern has indicated her intentions to look into how social media can be better regulated, Mouat noted that this can take time.

In the meantime, he says, New Zealand's brands do have the power to choose where they would like to put their money.

He stopped short of calling on more companies to pull ads from Facebook or Google, but said businesses need to seriously consider "if they wish to be associated with social media platforms unable or unwilling to take responsibility for content on those sites."

He took particular exception to live-streaming, which he said poses a massive risk of the same thing happening again.

Echoing the words of Spark managing director Simon Moutter on Twitter over the weekend, Mouat said he found it really hard to believe that more couldn't be done to moderate the content on social media sites.

"If the site owners can target consumers with advertising in microseconds, why can't the same technology be applied to prevent this kind of content being streamed live?" he asked.

Facebook and Google make hundreds of millions of dollars from digital advertising in New Zealand every year.

The latest figures from the Interactive Advertising Bureau showed that a total of $659.5 million was spent on search-based advertising in 2017.

Conservative estimates suggest that 90 per cent of that figure can be attributed directly to Google, meaning the company makes well in excess of half a billion dollars from its New Zealand advertising business.

The IAB figures showed that only $41.96 million goes to the social media category; however, this figure doesn't account for all the money spent through bookings directly with Facebook. An industry source suggested the difference is likely hundreds of millions of dollars.

A Facebook spokesperson said the company had "nothing to share at the current time," while Google is yet to respond to a request for comment.