Donald Trump has suggested deporting children who are U.S. citizens, along with their undocumented parents, as part of his plan to avoid separating families.

The U.S. President-elect has made it clear that, once in office, he intends to carry out large-scale deportations of undocumented immigrants. This has raised concerns about families where children are U.S. citizens by birth, but their parents are not.

In discussing his plans for mass deportations, Trump stated that families with undocumented parents and U.S.-born children would be deported together to avoid separating them.

“The only way you don’t break up the family is to keep them together, and you have to send them all back,” he explained.

When asked by reporter Kristen Welker whether this would include children who are legally in the U.S., Trump responded, “Well, what you’ve got to do if they want to stay with their father — look, we have to have rules and regulations.”

Welker’s question referred to the approximately 4 million mixed-status families in the U.S., where some members are legally in the country while others are undocumented.