The White House will announce as soon as Wednesday a Department of Homeland Security plan to return immediately all foreigners who illegally cross the southern border as part of the Trump administration's response to the coronavirus pandemic.

President Trump told reporters during a press briefing Wednesday afternoon the announcement was coming "very soon, probably today." Two Department of Homeland Security employees told the Washington Examiner the plan entails sending Mexicans who have been arrested for illegal entry back to Mexico within hours.

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Migrants who are arrested and then claim a credible fear of returning to their home country would not be exempt from the policy. Asylum seekers who show up at ports of entry are already returned to Mexico while they await the adjudication of their cases.

Mexican citizens make up the majority of people apprehended by Border Patrol agents, a major change in the demographic of immigrants taken into custody since last year's surge of hundreds of thousands of family members from Central America.

Customs and Border Protection did not respond to a request about the number of people it believes the new action could apply to. Last month, the Border Patrol reported arresting approximately 30,000 people who came over the southern border between ports of entry.