MH17 memorial service on August 7

A national memorial service for victims of the MH17 disaster will be held in Melbourne on August 7, Prime Minister Tony Abbott has announced.

The multi-faith service will be held at St Patrick's Cathedral.

"I hope many members of the public will attend to support the families of the victims," Mr Abbott told Fairfax Radio on Thursday.

Nearly 300 people, including 37 Australian citizens and permanent residents, died when a Malaysia Airlines plane was shot down over eastern Ukraine two weeks ago.

The service was being held in Melbourne because 16 of the victims came from Victoria, Mr Abbott said.

On the day of the service, flags on all Australian government buildings, here and overseas, will be flown at half-mast.

Arrangements have been made for an outside broadcast in anticipation of large crowds.