Immigration officers have plans to begin deporting about 1 million illegal immigrants that have already received court orders to leave the country.

Immigration and Customs Enforcement officers are hundreds of thousands of deportations behind schedule, Acting United States Citizenship and Immigration Services Director Ken Cuccinelli said on Sunday. ICE is expected to begin working on the backlog later this week.

ICE is obligated "to go and find, detain, and then deport the approximately 1 million people who have final removal orders," Cuccinelli told CBS Face the Nation host Margaret Brennan. Cuccinelli appeared on the program to defend the ICE deportations, which opponents have criticized as inhumane raids against immigrant families.

"[These migrants] have been all the way through the due process and have final removal orders," Cuccinelli said. "The pool of those with final removal orders is enormous."

The upcoming ICE roundups will not target all illegal immigrants with deportation orders. The roundups are expected to begin with a few thousand migrants.

ICE should be deporting immigrants with court orders on a rolling basis, but the agency has been stalled.

"[ICE officers] have been interfered with, effectively, and held up by the politics of Washington to a certain extent. They're looking forward to just getting back to doing their job," Cuccinelli said.