On Monday, the cabinet had decided it would be a Royal Commission Inquiry, which is "reserved for the most serious matters of public importance", the Department of Internal Affairs said on its website.
"It was originally meant to be a longer visit, including a business delegation, but under the circumstances that did not seem appropriate to be away for longer", she told reporters.
Ms Ardern said it would produce a "comprehensive" report.
New Zealand Prime Minister Jacinda Ardern waves as she leaves Friday prayers at Hagley Park in Christchurch New Zealand. Credit PA
"Thank you PM @jacindaardern and New Zealand for your honest empathy and support that has won the respect of 1.5 billion Muslims after the terrorist attack that shook the Muslim community around the world".
The interview, which aired Monday night in Australia, begins with Ardern asking Aly if she can give him a hug, saying she also saw his moving speech.
The minister in charge of New Zealand intelligence departments, Andrew Little, has denied suggestions authorities had not paid enough attention to far-right extremists and said an increased focus had been put on alt-right and white supremacy over the past year.
Ardern said she and other ministers would soon meet with Microsoft to discuss the role of social media following the sharing of live-streamed video of the alleged gunman's attack.
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Apple did reveal a short video, just over a minute long, that's sort of mega-trailer for Apple's upcoming original content. Apple watchers complained on social media that they could've done with less hype, and more actual clips from the shows.
Prime Minister Scott Morrison and opposition leader Bill Shorten will discuss the issue of violent online content with representatives from social media giants in Brisbane on Tuesday.
"But they do not point it out as an attempt to blame".
"Our job is to share love and support for our Muslim communities around the world", she said.
'The values of tolerance and inclusion and peace - those are New Zealand values.
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OR went to the Elite Eight for the second straight year last season but fell to eventual champion Notre Dame. If the Badgers are going to have a successful NCAA Tournament run they will need one man to carry the load.
The boy in the video says "To be honest with you, what brought me here it's you".
"This is not a world first, and so that is why our language is very deliberate".
Aly told The Project audiences seeing the memorial erected for the Christchurch terror attack victims was "almost life changing".
On the day of the Christchurch mosque shootings, Aly delivered a moving monologue on the TV show, which was shared tens of thousands of times and viewed millions more.
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Furthermore, a non-bailabl warrant has been issued by PMLA court against Ami Modi, wife of Nirav Modi. Raveesh Kumar, a spokesman for India's foreign ministry, said he welcomed the news of Modi's arrest.
In the last minutes of the interview, Ardern thanked Australia for their solidarity.