The White House is considering former Kansas secretary of state Kris Kobach and former Virginia attorney general Ken Cuccinelli for the position, a source familiar with the talks told CNN on Monday.

Earlier in the day, the Homeland Security Department in a press release said it is accelerating the deployment of up to 750 immigration officers to the US border with Mexico in emergency surge operations "to address the influx of migrants."

Last week, US Border Protection Commissioner Kevin McAleenan told reporters that encounters at the southern border were on pace to hit record highs in March.