Britt Lapthorne's father has spoken of his grief over the death of his "beautiful girl".

VIDEO: DNA confirms body is Britt

Dale Lapthorne and son Darren hope to return to Australia with Ms Lapthorne's body next week after Croatian police confirmed remains found off the cost of Dubrovnik last Monday were those of the 21-year-old backpacker.

"We're looking at Wednesday, Thursday shipping out - the sooner the better," Dale Lapthorne said.

"The hardest thing is going to be coming home. It's hard enough knowing that Britt will be there, travelling with us, but the hardest thing will be arriving home," he added as he fought back tears.

Ms Lapthorne's devastated mother Elke spent Saturday grieving at the family's Melbourne home after hearing the news of her daughter's death.

Convinced of foul play

Autopsy results, expected on Monday, could shed light on the cause of death, but her family are convinced she met with foul play.

"Assuming it is a crime, and everything is pointing to a crime, it is an absolutely heinous crime of the worst order," Mr Lapthorne said.

"It is just beyond conception for such a beautiful girl. I don't mean beautiful in appearance, she was beautiful in her ways - always smiling, always happy, just having fun. An intelligent, smart girl. Why could somebody do this to such a beautiful girl?

"And for me, and Elke and Darren, it's just devastating.

"We think of all the things we planned to do together. Although they're young adults, we still do things together.

"All the things we planned have no meaning anymore, absolutely no meaning."

Identity finally confirmed

Croatian police confirmed the identity of the body on Friday after earlier saying the level of decomposition meant it was unlikely to be Ms Lapthorne, who was last seen at a Dubrovnik nightclub in the early hours of September 18.

Mr Lapthorne on Saturday spoke of his shock when he was told the body was in fact his daughter.

"We were told the horrifying news," he said.

"I was so convinced it wasn't Britt. A lot of the police were convinced it wasn't Britt.

"I believe almost everybody was convinced it wasn't Britt, and then we're hit with this smack in the jaw, it was just unbelievable, unbelievable."

Mr Lapthorne refutes any suggestion his daughter jumped or fell off the cliff above the cove where her body was found, 18 days after she went missing.

Britt's shirt found

Meanwhile, Croatian daily Slobodna Dalmacija reported in its online addition that a shirt belonging to Ms Lapthorne was found on the side of a road six km west if Dubrovnik.

The newspaper said police found the shirt 50 metres from the main road close to the village of Stikovica.

Mr Lapthorne said he had been told by the media the shirt had been found, but a detective assigned to the case from the capital Zagreb checked it out with local police and was told it did not belong to the Australian.

"But the description we have, could be, could be," Mr Lapthorne said.

"We just don't know."

Meanwhile, Foreign Minister Stephen Smith says he's confident Australian consular officials did everything possible to find Ms Lapthorne.

Mr Smith said the confirmation that a body found floating off the city of Dubrovnik was Ms Lapthorne was a family's worst nightmare.

"We believe we did everything possible to render assistance to the family and we will continue to do that," he told the Ten Network.

"We have indicated we will provide every assistance to return Mr Lapthorne and his son to Australia together with Britt."

Authorities criticised

Family members have been critical of the response by both Australian and Croatian authorities.

Mr Smith said in such tragic circumstances, they were entitled to say whatever they wanted.

"They are going through a nightmare. I am not proposing to quibble with what they are saying publicly," he said.

"But I am confident in this case as in very many others that our consular official did everything humanly possible to render assistance to the family in what was a terrible and tragic circumstance," he said.

Mr Smith said the handling of the Lapthorne case would be reviewed in the normal course of events.

But he said nearly a million Australians were overseas at any time with some 50 currently listed as missing.

Mr Smith said providing assistance to Australians abroad, particularly in difficult cases where someone was missing, required the cooperation of the nation state.

"We worked very closely with the Croatians to make sure that no stone was left unturned to discover Britt and we are confident that occurred," he said.

"I am absolutely convinced that our officers from the first moment they were advised she was missing did everything they possibly could with the Croatian authorities."