Biden harbored concerns about what the sharp increase in migrants at the southern border meant for the government’s capacity to handle an influx of refugees from elsewhere, according to the people, who spoke on the condition of anonymity to share private deliberations. In the end, the president’s own misgivings fueled the decision more than anything else, the people said.

The president was particularly frustrated by the government’s struggle to deal with unaccompanied minors at the border and became increasingly concerned about the Office of Refugee Resettlement’s response to the crisis, the people said. The unit, housed at the Department of Health and Human Services, has responsibility for both unaccompanied minors at the border and the separate group of foreigners seeking refugee status due to persecution, war or oppression at home.