Democrats failed on Wednesday to block Republican attempts to cut billions of dollars in food assistance to poor American families, having earlier denounced the plans as an "abomination" and "immoral".

The Republicans included the $16bn (£10.3bn) cut to the food stamp programme over the next decade as part of a five-year farm bill debated in the House of Representatives agricultural committee. Democrats submitted an amendment to prevent the cuts but lost in a vote after a heated debate in which some members of Congress said more than 2 million people would lose food assistance under the programme formally called the Supplemental Nutrition Assistance Programme (Snap).

"You need to think of that child out there that's going to go hungry," said Democratic congressman David Scott. "This right here is the meanest cut of all. It's un-American. Twenty percent of my home state of Georgia is on Snap. Can you imagine what a $16bn cut will do?"

The Republican move appears to be intended in part to highlight Republican disparagement of Barack Obama as the "food stamp president" because record numbers of Americans now claim the benefit, doubling the cost of the programme since 2008 to $80bn a year. More than 46 million Americans receive food stamps, nearly half of them children.

The agricultural committee chairman, Frank Lucas, justified the cuts in part by claiming that the system had been manipulated by some US states so the federal government provided food to households not entitled to assistance.

"Snap's resources have been stretched because this administration has encouraged states to take liberties in how the programme is administered," Lucas said at the opening of the hearing to consider the bill.

"I'd like to be clear that this legislation will not prevent families that qualify for assistance under Snap law from receiving their benefits. We are working to better target the programme and improve its integrity so that families most in need can continue to receive nutrition assistance."

Republican Randy Neugebauer of Texas said false claims for food stamps was a major problem and claimed there had been cases of lottery prize winners receiving assistance.

"How can you look the American taxpayer in the eye and say we are going to look the other way with people who are gaming the system, with states that are gaming the system?", he said.

Democrats hit back by saying there was no evidence that fraud is a major problem. Some Democratic members of the committee told the hearing they had once relied on food stamps. "I wouldn't have been able to feed my son and my wife," Joe Baca, said.

Congresswoman Rosa DeLauro said a study by the Congressional Budget Office showed up to 3 million people would lose access to the programme and almost 300,000 children would lose access to free school meals.

She said: "These proposed cuts show a total disregard for the real impact they would have on hungry kids and families across the country … This is immoral. We have to stop these cuts. We cannot let American families face the threat of hunger."

Terri Sewell, a congresswoman from Alabama, called the cuts unconscionable. She said she recognised that the huge government deficit needs to be tackled but added: "We cannot do it at the expense of the very poor."

Congressman Jim Clyburn, the third most powerful Democrat in the House of Representatives, said: "For us to be marking up this farm bill with this big a cut in Snap programmes is an abomination.

"I know what it is to try and teach world history when you know the students in front of you did not eat breakfast. We should not set ourselves up as protectors of the wealthy, which seems to be what we are doing in this farm bill."

But after long debate, the amendment to remove the cuts from the farm bill was defeated by 31 votes to 15 with some Democrats siding with Republicans. Among them was the leading Democrat on the committee, Collin Peterson, who said the cuts had to remain in the legislation for now because it needed to ne approved by next month, in time to replace the existing farm bill, which expires in September. He has said he expects the Senate to remove the cuts to food stamps when it considers the bill.

"I remain concerned with the proposed changes to nutrition programmes. There are better, more responsible ways to improve and reform federal nutrition programmes; ways that would clean up some of the mess states have made with these programmes," he said. "However, the bottom line is that we need to move the legislation."

The legislation has met resistance from some Republicans who object to the cost of the $100bn-a year bill – 80% goes to the food stamp programme, but some is allocated to the price support that guarantees farmers minimum payments.

© Guardian News and Media 2012