MEXICO CITY — The Roman Catholic Archdiocese of Mexico City said Sunday that Mexican companies expressing interest in working on a border wall in the United States are betraying their country.

The archdiocese said in an editorial that Mexican companies have expressed willingness to supply materials or work on the wall proposed by U.S. President Donald Trump. Mexico opposes the wall.

The editorial was titled “Treason against the Homeland,” and said that “what is most surprising is the timidity of the Mexican government’s economic authorities, who have not moved firmly against these companies.”

In a meeting with steel companies in Mexico last week, Economy Secretary Ildefonso Guajardo said the government did not plan restrictions on businesses, but warned that Mexicans would judge and base future buying decisions on “which brands are loyal to the national identity, and which are not.”

“I think your prestige will align with your own interests in not participating in the wall,” Guajardo told the companies.

It is unclear how many Mexican companies have expressed interest in the wall.

The archdiocese, which is led by Cardinal Norberto Rivera Carrera, said Mexican companies have expressed interest in supplying cement, paint, lighting and other materials.

“Any company that intends to invest in the fanatic Trump wall would be immoral, but above all, their owners and shareholders will be considered traitors to the homeland,” the editorial said.