The Foreign Affairs Department has taken its relevance for granted and should be more prepared to make the case for additional funding and staff, according to Liberal MP and former diplomat Dave Sharma.
Mr Sharma, who entered parliament last year after a nearly 20-year career in the public service, said the Department of Foreign Affairs and Trade had assumed it was an indispensable part of government.
In a wide-ranging interview, he said DFAT should put its hand up and offer solutions to the government's challenges, while also promoting its value.
Mr Sharma, who joined DFAT in 1999 and worked there in multiple roles until 2017, believes it has failed in the Canberra bureaucratic struggle for resources, and says Australia's diplomatic service remains one of the smallest within the G20.
DFAT's budget had remained the same in 20 years despite the national security and international challenges of those decades, he said. Meanwhile, Australia had increased its defence spending, grown its national security apparatus, created the Department of Home Affairs, and boosted funding for intelligence agencies.
"You've got a situation where there's a whole lot more players in this national security, foreign space that are a whole lot better resourced than DFAT and have a whole lot more personnel and control of budgets, and DFAT's still has the same size, same budget, but with more competition, it has a diminished role," he said.
The causes could not be pinpointed to a single government, minister or secretary, Mr Sharma said.
"It's a bit more broad ranging and structural than that.
"Some of this is attitudinal. There is still a kind of an assumption within Foreign Affairs that they are an indispensable part of government, and that's true to a point, but that's been cut back to their indispensable role, whereas other departments and agencies are always, they don't take their positional relevance for granted so much, and they're prepared to fight a bit more.
"DFAT needs to fight more for its place at the table, it won't always be given it as a matter of right."
He said that as a public servant he saw other agencies come to the government with solutions to challenges, and make the case for additional funding.
"DFAT just hasn't done that. So it's not like anyone has set out to punish them, they just haven't had their hand out when the government's said 'we've got more resources'," he said.
"We really need Foreign Affairs to put up its hand and say 'we can do this for you, we've got a plan and we're going to do it this way, we're going to do it that way, we need more resources, but this is our vision, this is how we can give you a solution to this problem'.
"And I think that proactive, future-oriented posturing is what's really been lacking from DFAT over the past 20 years."
The Foreign Affairs Department this month told staff it would downsize by 10 overseas positions and 50 positions in Australia due to budget pressures.