House liberals are threatening to withhold their support of a carefully negotiated farm bill if it doesn’t make hikes in anti-hunger programs permanent.

Rep. James McGovern (D-Mass.) and other members of the Congressional Progressive Caucus organized a campaign to demand that House Agriculture Committee Chairman Collin Peterson (D-Minn.) push for permanent funding increases for food stamps and other programs when the farm bill goes to conference committee.

The letter, also signed by Reps. Rosa DeLauro (D-Conn.), Lynn Woolsey (D-Calif.), Barbara Lee (D-Calif.) and Hilda Solis (D-Calif.), seeks support for pressing Peterson to push hard for the House position in the conference negotiations.

The final letter, signed by 153 House members, was delivered Wednesday.

It could make negotiators’ work trickier, as the Bush administration has already threatened to veto the bill because of the tax change House negotiators used to fund the increase in anti-hunger programs sought by liberals. Moving the farm bill this year is a top priority for Speaker Nancy Pelosi (D-Calif.), who wants to protect vulnerable Democrats who represent rural and more conservative districts.

Both the House and Senate would increase funding in the farm bill nutrition title for food stamps and an emergency food assistance program that helps fund food banks.

But the House made the increases “permanent” by funding them through the 10-year budget window. The House “paid” for the added expense by ending a tax benefit for foreign companies, which led many House Republicans, even from rural districts, to vote against the farm bill on the House floor.

“We call it closing a loophole; Republicans call it a tax increase,” a Democratic staffer explained.

The Senate did not end the foreign tax benefit, and was only able to pay for increased funding for food stamps and assistance through a five-year budget window. That means that when the farm bill comes up again in five years, it will not be included in the baseline, which makes it more likely funding increases will then end.

“Simply, this means that these important policy improvements would return to today’s law, resulting in a major reduction in benefits to more than 10 million recipients,” the letter to Peterson said.

Senate Agriculture Committee Chairman Tom Harkin (D-Iowa) says they’ll get no argument from him in principle. He says it’s just a matter of finding the money.

“Unfortunately, budget shortfalls forced us to sunset provisions of the Senate farm bill in order to make overall numbers work,” said Harkin spokeswoman Kate Cyrul. “The chairman sees this as a problem that needs to be solved and hopes that the final conference package will include nutrition funding for a full 10 years.”