The government has cut $11.3 billion from the aid program since coming to office in 2013, slashing assistance to some of the world's poorest countries and leaving many long-running and successful programs in doubt.

And now it appears to be taking the axe to transparency too.

Experts are complaining that this year's budget papers contained far less detail than usual about aid. Chief among their concerns is the absence of a so-called "blue book", a ministerial statement that typically contains a wealth of information about how money is being spent, including country and regional allocations and reports on progress and results.

The government first failed to provide a blue book last year but later published the equivalent information in a document released online.

This year, the information has not materialised at all.

Marc Purcell from the Australian Council for International Development, the peak body for non-government aid and development groups, says the program is now more opaque than he's ever seen it.

"Transparency has really declined. I won't say transparency has completely evaporated but it's really hard now for Australians to see how their money is being spent," Mr Purcell said.

The budget did provide headline figures on how much money individual countries would get. But that's not enough information to give the public confidence that their money is being used appropriately, Mr Purcell says: "We know the dollars but we don't know what's being done with them."

A spokeswoman for Foreign Minister Julie Bishop says information previously provided in the blue book is now available on the Department of Foreign Affairs and Trade's website.

But Australia's leading aid academic, ANU professor of economics Stephen Howes, says that's not entirely true.

"The amount of information available on the web is in fact very uneasy and patchy – and in a lot of cases is just not there at all," he said.

Professor Howes, who heads up the Development Policy Centre, says aid transparency improved as the program scaled up under the Rudd and Gillard governments. But he says Ms Bishop's pledge to improve transparency further is going unfulfilled.

"Unfortunately it's gone in the opposite direction," he said.

"We learnt in the budget what countries are going to be affected – and that's important – but what really matters is what projects are going to be cancelled or downsized."

Ms Bishop's spokeswoman says more information about the aid program will be made available later in the year.

"Further information on priorities for significant country programs will be available in Aid Investment Plans following consultation with Australia's partner governments," she said.

Labor's foreign affairs spokeswoman Tanya Plibersek says the government's aid cuts have not only hurt some of the world's poorest people but have also put the region's security at risk.

"Julie Bishop has gone to extraordinary lengths to hide details of her $11.3 billion cuts because she is embarrassed about what the truth shows: that she presides over the weakest foreign aid program in Australian history," she said.

Australia's spending on aid will drop to just 0.22 per cent of gross national income in 2016-17 – the lowest level since records began.

Ms Bishop has also been accused of wanting to "pad out" the aid budget numbers by counting the cost of overseas military and security assistance, in contravention of OECD standards. But Ms Bishop says she wants those figures better reported, not included in the aid budget.