CCTV image of missing British tourist Grace Millane released by police

A new photograph showing the last known sighting of missing tourist Grace Millane has been released by police.

The blurry image - taken from CCTV security footage - shows the young woman dressed in a black dress and white shoes, with her brown hair down.

The image was captured on Saturday night, about 7.15pm, in downtown Auckland near SkyCity, police said.

It is the last time anyone has seen Millane, whose 22nd birthday was the next day.

Detective Inspector Scott Beard said police were dealing with her family in the United Kingdom and were expecting her father to arrive tomorrow.

Missing Brit Grace Millane, 22, is the daughter of millionaire David Millane. Photo / Supplied

"Her family member is coming out - obviously, they're distraught. They're on the other side of the world and they haven't heard from her."

Beard said there was no evidence of foul play at this stage and police were speaking with people at the backpackers Millane was staying at - including those she was with on Saturday night.

He would not confirm what was left at the room, but said her belongings remained there.

Millane, who has been in New Zealand for about two weeks, has travelled to the Bay of Islands since arriving.

She was due to leave New Zealand in about two weeks, police said.

More than 20 police staff are on the case, he said.

Police would not comment on her bank account or cellphone activity.

"The longer this goes on, the more worrying it is. At this stage we're hopeful we will find Grace."

Beard said they were still trying to get in touch with a number of people she had been with on Saturday night.

Millane's father, millionaire property developer David Millane, is due to touch down in Auckland tomorrow.

The CCTV image of Millane on Saturday night at SkyCity. Photo / via Police

Beard said having him here would allow officers to get to know more about Grace Millane's background.

"I'm sure he'll want to know, first hand, what the police are doing to try to find his daughter," Beard said.

New details have emerged about the background of a missing British backpacker and her time in New Zealand.

She was seen on Victoria St, in downtown Auckland, about 7pm.

It has since been revealed that Grace Millane, who has been in New Zealand for about two weeks, is the daughter of a millionaire property developer, David Millane, the Daily Mail reported.

The 60-year-old is due to touch down in Auckland tomorrow as fears for his daughter's safety continue to grow.

His wife, Gillian, is recovering from an operation and will stay back in the UK, the newspaper reported.

Grace Millane, who graduated from the UK's University of Lincoln this year, reportedly saved for her trip to New Zealand by working at her father's company.

A talented artist, Millane has shared a number of her works - watercolour pieces - on a dedicated Facebook and Instagram page.

She also sold a number of paintings to help fund her big overseas trip - which included a journey to Lima, Peru, and Machu Picchu.

A message she posted on Twitter, on November 19, read: "Of course it's raining when I arrive in New Zealand.''

Last Thursday, November 29, she posted: "I think travelling has changed me I just bought some blue jeans." [sic]

That last post now has messages from people calling for her to get in touch with her family.

View this post on Instagram

☔️ #watercolour #art

A post shared by Grace Millane (@art_by_millane) on Jan 30, 2018 at 10:55am PST

"Hope you are okay. Your friends and family are looking for you x please contact them if you can so they know you are ok. sending all my love to you.'' [sic]

Another has written: "Hey lady! Where are you? Everyone is worried. Please make contact with your friends and family.''

Millane's brother, Michael Millane, posted on social media that the family had been calling his sister's cell phone - but that it was going straight to voicemail.

He said she had been staying at X Backpackers - which she described as a "party hostel'' - and had been sharing a room with two other girls and a boy.

"She spoke to someone in the family every day on WhatsApp, Facebook or FaceTime. The contact with us stopped on Thursday.

"The last contact she had was with her roommate on Saturday morning.

"Her disappearance was completely out of the blue."