President Trump will announce his plan on Tuesday to relax restrictions on selling more ethanol into the nation's gasoline supply, while also cutting costs for refiners.

The first part of the plan would allow 15 percent ethanol fuel blends, or E15, to be sold year-round, instead of being excluded from the summer driving season, according to an administration official who previewed the announcement on Monday.

The plan is being rolled out as Trump goes to Iowa to hold a midterm election rally and gain support from farmers. Corn growers and their supporters have been clamoring for the plan to counter low crop prices and new tariffs on U.S. agriculture products by China and the European Union. Upping E15 sales would bolster demand for corn by helping to expand the market for corn-based ethanol.

“We’re very excited to hear the president’s upcoming announcement," said Emily Skor, president and CEO of Growth Energy, a top ethanol lobbying group in Washington. "He knows farmers are hurting and they want action on E15 in time for the next summer driving season."

Since the fuel can be sold eight months out of the year, the administration’s goal is to have the Environmental Protection Agency finalize its rulemaking for the plan by next summer’s driving season in June, the official said. EPA has yet to unveil its official timeline for the regulation.

President Trump on Tuesday will direct EPA acting administrator Andrew Wheeler to undertake a rulemaking that addresses two specific areas of the nation’s renewable fuel program, the official explained.

First, the EPA is to expand the Reid vapor pressure waiver to fuel blends with up to 15 percent ethanol, which will allow for the sale of E15 year-round, the official said.

Second, EPA will take actions to help stabilize the unregulated market used by refiners to buy renewable identification number credits, or RINs. Refiners use the market to comply with the EPA Renewable Fuel Standard program, which they argue has caused significant increases in the cost of doing business.

The RIN stabilization effort will be done “by taking actions to limit manipulation and provide for additional transparency,” the official added.

The RIN market reforms appear to be the largest piece of the plan. At least four separate actions will be part of the market reform effort.

The actions target market manipulation by traders and others, which in the past have led to price spikes in the cost of RINs. The refinery industry argues that the higher price of RINs has made it harder for them to turn a profit and remain economically solvent. It is also a prime reason why President Trump began sitting down with both refiners and ethanol producers a year ago to devise a “win-win” solution that both industries could live with.

The only problem is that the oil industry and refiners don’t want Trump to allow the year-round sale of E15, which they say will harm consumers’ vehicle engines that are not compatible with the fuel.

The American Petroleum Institute and the American Fuels and Petrochemical Manufacturers, representing the oil industry and refiners, sent a letter to Trump last week, advising him not to move forward with the plan, and instead work with Congress on a plan to reform the program.

The only way the oil groups say they would agree with Trump’s plan is if it called for EPA to sunset the renewable fuel program in 2022.

The senior administration official said the president has long-supported the EPA’s Renewable Fuel Standard program. The president thinks it is good to have domestically produced energy, “and thinks this will actually be good for the agriculture industry, as well as the economy overall,” the official said.

The official also said that the president’s E15 plan is “in line with the president’s free-market approach to the energy market” when it comes to providing more consumer choice.

When asked about the impact of the plans on climate change, the official said the plan is not “directly related to climate change.” The official was making a distinction between action meant to promote biofuels and actions associated with countering the effects of global warming.

When pressed on the issue, the administration official said the president's plan is in line with policies that have reduced U.S. emissions 14 percent over the last decade.

“From 2005 to 2017, the United States’ carbon dioxide-related emissions have declined by 14 percent,” the official said. That’s compared to the rest of the world that has increased its carbon emissions by 21 percent during the same period, the official added.

“This has been possible through the development and large scale deployment of new, affordable, and cleaner technologies to capitalize with our energy abundance, and this action is in line with that policy,” the official explained.