UPDATED 3.45PM: Muhammad Rizalman has pleaded guilty to indecently assaulting Wellington woman Tania Billingsley.

The former Malaysian defence attache who returned to New Zealand to face criminal charges has this morning admitted indecently assaulting a Wellington woman.

The charges relate to events that allegedly happened at a home in the Wellington suburb of Brooklyn in May last year.

Muhammed Rizalman bin Ismail, 39, was to have faced trial in the High Court at Wellington toady, but has admitted a charge of indecently assaulting Tania Billingsley.

Crown prosecutor Grant Burston offered no evidence on a charge of assault with intent to sexually violate Ms Billingsley, while a charge of burglary was dismissed.

As Rizalman stood in the dock, a Malay interpreter helped him.

Meanwhile, the Government's being warned it's out of excuses to hide information on the case.   

Labour's foreign affairs spokesperson David Shearer said the court case has been used as a shield to not answer questions on how Rizalman was first allowed to claim diplomatic immunity, and leave the country. 

"As soon as something like this it's swept under the carpet, we can't get answers."

Mr Shearer said at the very least Ms Billingsley deserves answers. 

"She's gone through the mill on this and I think the government needs to understand that."