A decreased emphasis on climate change and cuts to the foreign aid budget under the Abbott government caused a loss of expertise, a lack of oversight and early closure of some projects, according to an internal government report.

Two-thirds of selected projects by the Department of Foreign Affairs and Trade achieved a modest or significant impact on climate outcomes, the evaluation said.

But despite Australia spending $599m on climate-related aid investments between 2010 and 2013, the report said that the resourcing of such projects then began to decline.

“From this time to the Paris Agreement at the end of 2015, Australia did not provide dedicated additional climate financing, with climate action subsumed into general aid programming.”

Although the report does not mention the 2013 election of the Abbott government, it says there was “a loss of climate-specific expertise from the aid program as funding and priorities changed”. It adds that programming choices were “decentralised to posts which also had to manage reductions in the broader aid program at this time”.

In some cases “climate change investments were rebranded in 2014 (for example, as food security, water security or disaster preparedness), as climate was de-emphasised in the Australian policy context”, it said.

“Staff and senior managers spent a considerable amount of time internally rebranding the work and many lost the ability to report on climate-related outcomes as these objectives and indicators were removed,” it said.

“Many other investments lost impetus and were closed early as staff incentives abated.”

The Abbott government cut foreign aid by a total of $11bn over the medium term, reducing Australia’s aid program to the lowest levels since the creation of a formal aid program more than 40 years ago.

At the Paris climate conference in December 2015, Malcolm Turnbull announced Australia would provide at least $1bn over five years to build climate change resilience and reduce emissions in developing countries.

The evaluation examined a sample of 26 projects valued at $641.2m that started between 2006 and 2014. It found that nine projects achieved or were likely to achieve “significant climate-relevant outcomes” and a further nine would achieve “modest” outcomes.

The remaining eight projects were either unlikely to or would not achieve climate outcomes or were not designed with climate outcomes in mind.

The report said the majority of investments “proved effective” but there was less evidence that the results would achieve climate outcomes because “monitoring and the subsequent reporting of climate change results was often inadequate and inconsistent”.

The department elevated climate change as a priority for aid in July 2016, but the report said its strategy and implementation plan was scheduled for completion this year.

In addition to completing this plan, the report recommended the department routinely collect information to track the effectiveness of its climate change investments and strengthen internal design and staff capacity for climate change projects.

In its response, the department said the report contained “valuable analysis and insights that can directly inform more effective climate change action”.

“The department agrees broadly with all the evaluation’s recommendations and with its conclusions.”

The Australian Council for International Development’s development economics adviser, Amrita Malhi, said the evaluation showed that up to 2013 Dfat’s efforts on climate change action were “bearing fruit” but then climate objectives were “stripped out and investments closed down”.

“After five years, it is only now that there are early signs of recovery and climate change is being considered as a more important component of the aid program,” she said. “Compared to our allies, like the UK, we are now playing catch-up.”