The man accused of murdering British backpacker Grace Millane left her dead body in a suitcase in his flat while he went on a Tinder date, a court has heard.

Ms Millane, 22, from Wickford in Essex, was in New Zealand on a round-the-world trip last year when she was allegedly strangled by the 27-year-old, who cannot be named for legal reasons, during rough sex at his apartment.

The pair had met on the dating application Tinder and gone out drinking together in Auckland city centre.

The suitcase containing her remains was found in a shallow grave in a forested area of the Waitakere ranges a week later on December 9.

Opening the case at Auckland High Court today, prosecutor Robin McCoubrey claimed that the defendant had "contorted her body" into a suitcase then gone on another Tinder date, seemingly "unconcerned by the dead body in his apartment".

Mr McCoubrey said he had also carried out a number of incriminating internet searches in the moments after Ms Millane was killed, including "large bags near me", "rigor mortis" and the mountainous area where she was discovered.

"It's plain that Ms Millane is dead at that point," said Mr McCoubrey. "What the defendant is trying to do is find a place to dispose of her body."