President Trump’s budget proposal would dramatically change federal law, effectively giving the White House power to reject and modify food and tobacco regulations decided by the Food and Drug Administration.

Mr. Trump’s spending plan for the 2020 fiscal year would end all FDA authority over tobacco products, including cigarettes and other tobacco products like cigars and hookahs. It would retain authority over alcohol and drugs and medical devices, but completely exempts tobacco products from their jurisdiction.

The move would be significant because the FDA already regulates tobacco products. But Mr. Trump’s budget proposal would strip out that regulatory authority, allowing the FDA to focus only on tobacco safety and prevention programs.

The spending plan and accompanying budget strategy proposal by Mr. Trump’s budget office also propose scrapping longstanding FDA regulations governing the labeling of food, touching off a fresh battle with the food industry.

Since 1930, the FDA has done so with the help of a method called “allotment authority,” which allows the agency to require certain disclosures or “warning statements” on food products, as well as certain ingredients or marketing tactics that the agency deems unfair or deceptive.

The budget proposal would deregulate this process, allowing the agency to dismiss all rules as dangerous, even if they have been in place for decades.

Mr. Trump’s proposal would end all allotment authority for food labeling and prevent the FDA from imposing unfair and deceptive labeling on food products, though it would also give the agency more authority to crack down on fake labeling.

The Agriculture Department would remain in charge of ingredient labeling and consumer food labeling programs, with oversight at the FDA and USDA.

Just because the food and cigarette regulations are being abolished, that does not mean they will be immediately repealed. The budget proposal does not have any funding for the agency, but it lays out an “America First Food Policy” that calls for the elimination of all government regulations of all kinds, except those considered essential or necessary.