Prime Minister Scott Morrison announced the royal commission this afternoon after months of campaigning by bereaved families and pressure from across the political spectrum.

Mr Morrison expects the powerful inquiry to take between 18 months and two years to complete from July, with draft terms of reference to be reviewed over the next four weeks.

Wagga Defence Shed president Jason Frost said the royal commission could "provide [the Department of Veterans' Affairs] with the answers to some of the problems" faced by former service personnel.

"I hope the royal commission first and foremost helps curb some of the chronic issues that the community are facing, obviously suicide number one," Mr Frost said.

"And I think the key is to look at the clinical research [on new medical treatments]. We've got clinical research from around the globe that the DVA has as well."

Mr Frost hopes the DVA explores newer treatments for chronic health issues faced by veterans, such as medical cannabis.

Wagga RSL Sub-Branch president David Gardiner said the royal commission was "certainly warranted and certainly required" to help veterans struggling with the transition to civilian life.

"One of the main problems that I see with the mental health issue is that there aren't enough mental health [professionals] who can cater for what's needed out there in the community," he said.

Veteran Des Carmody said he supported the royal commission as long as the National Commissioner for Defence and Veteran Suicide Prevention, a role announced by Mr Morrison in February, retained the powers to investigate fully the matters that are referred to him or her.

He said veterans had been "let down phenomenally" by the system.

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