Aides say members of the House Agriculture Committee are unhappy with how Chairman Collin C. Peterson has handled this year’s farm bill so far.

The dissatisfaction intensified last night, aides said, when Peterson told panel members that his draft of the legislation would spend all of a proposed $20 billion “reserve fund” that was meant to pay for new initiatives. The announcement complicated today’s subcommittee markup of portions of the bill. Members withdrew numerous amendments because of the budgetary constraints. The Conservation, Credit, Energy, and Research Subcommittee is expected to continue its markup of the $3.8 billion conservation title of the bill throughout Tuesday afternoon.

Peterson, D-Minn., told members last night that he had spread out the $20 billion cushion across the draft bill’s 10 titles, but he would not tell members where it would go, according to aides.

The announcement frustrated both Democrats and Republicans who were counting on those funds to support new programs.

The committee can spend the extra $20 billion as long as the cost is offset somewhere else in the budget. The House leadership, however, has made no promises that it has found sufficient offsets.