President Trump’s campaign to slow down immigration took a new turn Tuesday: the administration plans to close all 21 international offices of the U.S. Citizenship and Immigration Services.

The move “could slow the processing of family visa applications, foreign adoptions and citizenship petitions from members of the military,” reports the Washington Post.

In an email, USCIS Director L. Francis Cissna told his staff that he wants to shift the work now performed by those offices to domestic offices and to U.S. embassies and consulates.

“He wrote that if the State Department agrees, the agency would move to close its international field offices in coming months ‘in an effort to maximize our agency’s finite resources,’” the Post says.

Cissna said he also plans to consolidate the agency’s domestic field offices.

The USCIS describes its mission as “Reuniting families, enabling adoptive children to come to join permanent families in the U.S., considering parole requests from individuals outside the U.S. for urgent humanitarian reasons or significant public benefit, and providing information services and travel documents to people around the world.”