Updated 4:40 p.m. Eastern

The Trump administration on Friday rejected a report of a plan to mobilize up to 100,000 National Guard troops to detain unauthorized immigrants.

The Associated Press reported a draft memo was under consideration indicating "millions" of immigrants could be affected in 11 states, not necessarily near the Mexico border.

"That is 100 percent not true," White House Press Secretary Sean Spicer said, according to a pool report. "It is irresponsible to be saying this."

He said, "There is no effort at all to round up, to utilize the National Guard to round up illegal immigrants. I wish you guys had asked before you tweeted," he added.

A reporter for The Associated Press said the organization repeatedly asked the White House for comment prior to publishing the story.

"I don't know what could potentially be out there, but I know that there is no effort to do what is potentially suggested," Spicer said. "It is not a White House document."

The AP reported the 11-page memo dated Jan. 25 was written by John Kelly, secretary of the Homeland Security Department and a former Marine Corps general, and addressed to the then-acting heads of U.S. Immigration and Customs Enforcement and U.S. Customs and Border Protection.

A copy of the memo posted online calls for expanding a program to include state Guard units in the border region. The so-called 287(g) program, part of the Immigration and Nationality Act, authorizes the use of such personnel "to investigate, identify, apprehend, arrest, detain, and conduct searches of an alien for the purposes of enforcing the immigration laws," it states. The effort has identified more than 402,000 potential people for removal in an almost 10-year period through September 2015, according to the document.

"I am directing the Commissioner of CBP and the Director of ICE to immediately engage with the Governors of the States adjacent to the land border with Mexico and those States adjoining such border States for the purpose of entering into agreements under section 287(g) of the INA to authorize qualified members of the State National Guard, while such members are not in federal service, or qualified members of a state militia or state defense force under the command of the Governor, to perform the functions of an immigration officer in relation to the investigation, apprehension, and detention of aliens in the United States," the memo states.

A spokesman for the Homeland Security Department said the AP report wasn't accurate. "It's incorrect," David Lapan, the spokesman, said in an email. "The Department is not considering mobilizing the National Guard for immigration enforcement." In a follow-up email, Lapan said Kelly didn't author any memo outlining such a plan.

An unidentified department official told The New York Times the document was an early draft that wasn't reviewed by the secretary.

Sarah Sanders, a White House spokeswoman who discussed the matter with reporters on Air Force One en route to Florida, said, "Secretary Kelly did not draft that memo," according to a separate pool report. When asked who drafted it, she said, "I'm not aware of the specific person, but I know that it wasn't Secretary Kelly or at his direction."

Spokespeople for the Defense Department, Army National Guard and Air National Guard said they weren't aware of the proposal.

The U.S. military has roughly 441,000 members of the Guard, including 335,000 in the Army National Guard and 106,000 Air National Guard, according to Pentagon budget documents from fiscal 2017, which began Oct. 1.

The Guardsmen are part of an overall military force of about 2 million troops across the active and reserve components.

An estimated 11 million people live in the U.S. without authorization, according to the AP.

-- Hope Hodge Seck, Richard Sisk, Matthew Cox and Oriana Pawlyk contributed to this report.

-- Brendan McGarry can be reached at brendan.mcgarry@military.com. Follow him on Twitter at @Brendan_McGarry.