House leaders signaled this week that they may choose to postpone until the fall a potentially nasty internecine floor fight on vehicle fuel-mileage standards.

House Majority Leader Steny Hoyer (D-Md.) said Wednesday that higher fuel-mileage standards would be a part of any energy bill that is sent to the president, although they may not be allowed on the House floor as an amendment to this month’s energy package.

“Any bill that goes to the president will include [vehicle mileage] standards very close to the Senate provisions,” Hoyer predicted. Hoyer said leaders could decide to wait until conference to add them, given that the Senate has already included a 35-miles-per-gallon standard for cars and trucks.

That move would avert a messy floor fight for now. The Senate-passed standards are backed by Speaker Nancy Pelosi (D-Calif.) and Hoyer and most Democrats, but opposed by House Energy and Commerce Chairman John Dingell (D-Mich.).

Dingell warned Wednesday that the Senate provision has “serious defects” that could cost jobs. Dingell said he is drafting his own proposal that would cause the industry to increase fuel economy as much as is feasible without costing jobs. One key issue, Dingell said, was that the Senate bill doesn’t take into account that domestic automakers sell a greater percentage of trucks and would thus be put at a disadvantage to foreign nameplates unless a separate truck mileage standard is maintained.

“I’m hearing that from the automakers and the UAW,” Dingell said. “I’m primarily concerned about the workers.”

Republicans, meanwhile, said there should be a full debate on vehicle fuel-mileage standards on the House floor and criticized House leadership for preventing Dingell from moving energy legislation that would have included such proposals as boosting coal-to-liquid technology and nuclear power.

“What happened is the Democratic leadership stifled the ability of the process to work,” said Rep. Dennis Hastert (R-Ill.), who said he feared delaying big but controversial energy issues to the fall means they might not get done.

Hastert said there should be “common-sense” vehicle mileage standards, and he praised Dingell. “His worry is he has 400,000 jobs in Michigan and if we don’t have common-sense standards, 400,000 jobs are going to go offshore.”

Energy and Commerce ranking member Joe Barton (R-Texas) said vehicle mileage standards shouldn’t simply be slipped into a conference report, given the potential to shut down American companies.

“You at least ought to have a debate on that and a vote on that on the House floor,” he said.

Pelosi has come under increasing pressure from environmental groups to quickly adopt a vehicle mileage standard given the Senate’s faster action — a rarity for that chamber — and to roll Dingell. The White House also has urged Pelosi to act this month on higher vehicle standards. But rewriting the House energy package in the Rules Committee and on the floor would get messy given that Dingell wants to wait until September to craft his broader global warming bill. Pelosi has said she wants an “open” debate on this month’s energy package but has not said whether it will include vehicle standards.

Dingell also has said he will float a carbon tax and increased gas tax to show how unpopular they are with the public.

House Oversight and Government Reform Chairman Henry Waxman (D-Calif.) said Wednesday he supports a carbon tax but doesn’t think passing one is realistic. Waxman said other ways of reducing carbon emissions, including a cap-and-trade system, mileage standards and other regulations, could be crafted instead.