The Prime Minister won't confirm whether convicted drug smuggler Karel Sroubek will have his residency revoked but says she's expecting the results from the investigation this week.

Immigration New Zealand is set to finish their report on the Czech smuggler's case "very soon".

Jacinda Ardern told Mike Hosking she can't comment before the report is released.

"I'm not comment on that until we release the final outcome...I'm not going to jeopardise any of the elements of this case before we put it out."

She said they are "finalising some of the legal details" but that doesn't mean he is being kicked out. 

The Prime Minister said she still has full confidence in the Immigration Minister Iain Lees-Galloway, saying he won't lose his job.

"There was contradictory information in the public domain compared to what was put before the Minister - that was the whole point of Immigration New Zealand going back to Sroubek's lawyer." 

She said they will "stand by" the final outcome of the report.

However, she said she isn't satisfied with the immigration process and will be looking at making necessary changes.

"I also need to make sure that looking forward, the way that we handle these individual cases, which are complex, I',m not particularly satisfied with the process that has been applied over a number of years. When I look at the position we have put Ministers in, I think we can do better."