Kamala Harris will lead efforts to control the surge of migrants at the southern border, giving the vice president leadership over one of the administrations most high-profile challenges.

This new surge we are dealing with now started in the past administration, but it is our responsibility, President Joe Biden said Wednesday. He added that he could think of nobody who is better qualified to do this.

The migration challenge is the first issue Biden has publicly asked Harris to lead, and its one he oversaw while serving as vice president under Barack Obama .

Bidens administration has been facing criticism from both parties over the unaccompanied children and teenagers coming across the U.S.-Mexico border, particularly for the crowded facilities where they are being held.

There are more than 14,000 migrant children in federal care right now.

Department of Homeland Security Secretary Alejandro Mayorkas has acknowledged that the U.S. is on pace to encounter more individuals on the southwest border than we have in the last 20 years.

Harris will oversee the administrations diplomatic efforts with the Northern Triangle countries El Salvador, Guatemala and Honduras and work with them on both short- and long-term solutions to reduce migration to the United States. Her focus will be addressing the root causes that push people to come to the country.

In an interview with CBS on Wednesday before the announcement, Harris said she and Biden will go down to the border at some point, emphasizing that solving the problem will not happen overnight.

Look, weve been in office less than 100 days, she said. We are addressing it. Were dealing with it. But its going to take some time. And are we frustrated? Are you frustrated? Yes, we are.