Feb. 27, 2013 -- The looming budget sequestration will make Americans less safe, Eric Holder says—and anyone who says otherwise isn't telling the truth.

"This is something that is going to have an impact on the safety of this country," the U.S. attorney general told ABC's Pierre Thomas on Wednesday in a wide-ranging, exclusive interview.

"And anybody that says otherwise is either lying or saying something that runs contrary to the facts," Holder said.

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In his interview with ABC News, Holder reiterated warnings that if automatic spending cuts are triggered on Friday, the Justice Department will be handicapped in some of its most vital missions to prevent terrorist attacks and crime.

"The Justice Department is going to lose nine percent of its budget between now and September 30th. We're going to lose $1.6 billion. There are not going to be as many FBI agents, ATF agents, DEA agents, prosecutors who are going to be able to do their jobs," Holder said. "They're going to be furloughed. They're going to spend time out of their offices, not doing their jobs."

President Obama's Cabinet members have been warning for weeks that budget sequestration, which will begin Friday unless Obama and Republicans reach a deficit-reduction deal to avoid it, will leave their agencies shorthanded and could bring about disastrous consequences. Homeland Security Secretary Janet Napolitano and Transportation Secretary Ray LaHood have both appeared at the White House press briefing room to warn that furloughs for border-patrol agents, TSA agents and air-traffic controllers will mean weakened border and port security, longer waits in airport security lines, and logjammed air travel.

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Holder, for his part, warned in a Feb. 1 letter to the Senate Appropriations Committee that cuts to the FBI, the ATF, the U.S. Marshals Service, and U.S. Attorneys would limit the department's capacity to investigate crimes. Cuts at the Bureau of Prisons, Holder wrote, would mean lockdowns and potential violence, with fewer staff members on hand. In a separate letter, FBI Director Robert Mueller warned that counterterrorism operations would be affected, with the possible elimination of some joint terrorism task forces with state and local police. Limited surveillance and slower response times would mean unwatched targets and the possibility that individuals on terrorism watch lists could gain entry to the U.S.

"FBI's ability to proactively penetrate and disrupt terrorist plans and groups prior to an attack would be impacted," Mueller wrote.

To Holder, the problem is simple.

"If you don't have prosecutors and agents doing what we expect them to do, and we won't if this thing actually takes place, we are going to be a nation that is going to be less safe. And that is simple fact," Holder said.

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Some Republicans have claimed the Obama administration is exaggerating the sequester's purported consequences as a ploy to campaign for tax hikes. On "Fox News Sunday" this week, Sen. Tom Coburn, R-Okla., posited that federal agencies enjoy enough flexibility to avoid the worst consequences of the cuts.

On Wednesday, Holder acknowledged that the Justice Department will do what it can to avoid compromised security, while maintaining that furloughs can't be avoided.

"We will try to minimize the harm, but the potential is there and the reality is that this Justice Department will not be as capable as it is right now if this sequestration goes into effect and if it lasts for an extended period of time," Holder said.

The 2011 Budget Control Act, which mandates sequestration in lieu of a broad deficit-reduction agreement, requires even cuts across the board. According to the Office of Management and Budget, that means even cuts to federal programs, leaving agencies mostly unable to rearrange money and cut their budgets in less harmful places.

"Every component is going to have people who are going to be furloughed," Holder told ABC News, noting that preventing terrorism will be "obviously our first priority, to make sure that we keep the American people safe and free from threats from outside our borders. We'll do the best that we possibly can."

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