Jacinda Ardern says the public shouldn't judge her Government on how it's handled the Karel Sroubek affair so far.
Instead, she told Newshub Nation on Saturday everyone should wait and see how they fix up the mess.
"When you're in Government, you have in front of you decisions that are made every day that we must act with caution, do our best to get right every single time - but there will be occasions when errors do occur and mistakes will be made," the Prime Minister told host Emma Jolliff.
Sroubek came to New Zealand in 2003 on a false passport, and built a career as a kickboxer. But he also developed connections with the underworld, which ultimately ended in his jailing in 2015 for importing MDMA.
The case hit headlines when it was reported Immigration Minister Iain Lees-Galloway cancelled Sroubek's automatic deportation order, which would have seen him sent back to the Czech Republic once his prison term was up.
Mr Galloway has refused to explain why, citing privacy and legal reasons. But he now says new information has come to light, and it contradicts what officials had presented to him before, so the case is back under review.
"Neither of us are satisfied with the long timeline around going back and looking at what's happened in this case," said Ms Ardern.
"We both want to see resolution quickly and answers quickly, and officials are understandably working as quickly as they can. I'm hoping and expecting we will get a response very, very soon."
She doesn't believe the controversy around the case, which has dominated headlines for a week, will hurt the Government in the eyes of the public.
"Ultimately the response from the public will be given that we've provided additional information, how do we act on that? How do we fix, if indeed an error has occurred, how do we fix that? That's rightly what we should be judged on. There have been cases like this in the past - I've had raised with me cases involving sex offences under the last Government, 100 of these kinds of cases."
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Mr Galloway has been accused of placing the blame for the controversial call on his officials.
"The fact that the minister is now throwing them under a bus, and implicating them in his terrible decision I think is an indictment on the minister," former Immigration Minister and National MP Michael Woodhouse told RNZ.
Ms Ardern denied this.
"I don't say that to place blame - that's just the reality of how the process works. For instance, under the last Government there were in the order of 100 of these kinds of decisions that were made. In each of those cases, ministers would have relied on what was provided to them."
She wouldn't express confidence in Immigration officials until seeing what information on Sroubek they come up with this time.
"I'm not going to predetermine that until we get the information back. At the moment obviously I don't have confidence in the decision."
The Czech Republic is reportedly preparing to seek extradition for Sroubek, saying he's wanted on outstanding criminal charges.