"We'd been hoping to have scaled up our seasonal relief operations... In the coming months with distributions of food and, in some areas, cash," Tomson Phiri, WFP spokesman in Zimbabwe, said as the country enters the peak of the so-called hunger season.
But "we've had to cut rations for one million of our beneficiaries in recent months and there are likely to be deeper cuts as from next month," Phiri said in a statement.
Food prices have doubled since last year, forcing many more into hardship, according to the WFP.
The UN food agency needs USD 80 million to feed hungry Zimbabweans in the next six months.
Also Read
So far it has just USD 20 million and is working at raising the remaining USD 60 million, WFP regional spokesman David Orr told AFP in Johannesburg.
"Our operational funding for the next six months is about USD 80 million and so far we are only a quarter funded," said Orr.
WFP is "very concerned about the food security situation in rural areas right now," he added.
Last week, the cash-strapped government of President Robert Mugabe said it would import 150,000 tonnes of the staple corn from neighbouring countries to avert food shortages.