Mexico released a list of U.S. products that could face a retaliatory tariff in response to possible Trump Administration tariffs that are scheduled to start this Monday on Mexican imports.

A Reuters report says the focus appears to be on states that supported Trump’s bid for the presidency.

However, the list doesn’t include corn, one of Mexico’s biggest imports.

Mexico’s rapidly-growing livestock industry relies on millions of tons of U.S.-grown yellow corn annually.

Industry experts say it would be extremely difficult for Mexico to replace American corn with imports from other countries quickly enough to fill the gap.

President Trump has said he’ll apply the first round of tariffs on all Mexican imports starting next week if Mexico doesn’t take steps to help stop the flow of Central American immigrants seeking entry into the United States.

Four anonymous Mexican government officials told Reuters that the list was prepared by the economy ministry and is sitting in President Lopez Obrador’s office.

Mexico’s retaliatory tariffs focus on states that voted for Trump in 2016, where agriculture plays a major role in the economy.

The tariffs are also targeted at several industrial states like Michigan, Pennsylvania, and Ohio.