Washington ? The government’s food aid programs are spending more and delivering less to hungry people than they could, according to a Government Accountability Office report released Thursday.

The reason: U.S. agencies buy commodities here and ship them on high-cost U.S.-registered ships. Countries that buy food aid locally in sub-Saharan Africa and Asia, the GAO found, deliver it for about a third less.

In addition, U.S. aid shipments reached their destinations in an average of 147 days, compared with 31 to 41 days for food bought locally.

While the U.S. remains the world’s largest aid donor in cash terms, its $2 billion in food aid buys 54 percent less food than it did in 2002, largely due to higher commodity and transportation costs.

Other major donors, including the European Union, the United Kingdom and Canada, have begun to donate cash directly to the World Food Program, which then buys food locally.

Buying locally also often helps developing countries to build their agricultural sectors, said Thomas Melito, the director of the GAO’s international affairs and trade team.

The U.S. would find the switch to local aid-buying politically difficult because farmers and shippers traditionally have been crucial to the coalition that backs foreign aid.

The House of Representatives Subcommittee on Africa and Global Health, which commissioned the report, praised GAO’s findings, but the power to change aid practices remains largely with House panels focused on agriculture and transportation.