The Justice Department says it is canceling negotiations with Arizona Sheriff Joe Arpaio's office over civil rights allegations against him -- claiming the sheriff refuses to include a court-appointed monitor in the process.
An agency spokeswoman said the Maricopa County Sheriff's Office knew the monitor was “a non-negotiable requirement of a settlement” and that the refusal has led to the cancellation of talks.
The move was expected, with the Justice Department saying Tuesday evening that Arpaio had initially agreed to the monitor, then failed to negotiate “in good faith” by changing his mind that morning.
“We believe that you are wasting time,” the agency said in a letter to Arpaio’s lawyer. “Your tactics have required DOJ to squander valuable time and resources.”
Arpaio, the self-proclaimed America’s toughest sheriff, has said he never agreed to the monitor because that would mean every policy decision would have to be cleared through an observer and would nullify his authority as the elected sheriff.
"I am the constitutionally and legitimately elected sheriff, and I absolutely refuse to surrender my responsibility to the federal government," Arpaio said, accusing the Obama administration of trying to "strong arm" him.
The Justice Department said both sides met at least once in February and that the letter marks the second time negotiations were called off, which means the agency will go forward with a lawsuit.
The agency has accused Arpaio's office of racially profiling Latinos, basing immigration patrols on racially-charged citizen complaints that did not allege crimes and punishing Hispanic jail inmates for speaking Spanish. It also accused the sheriff of having a culture of disregard for basic constitutional rights.
The sheriff's office has denied allegations of systematic discriminatory policing and told news reporters that it will insist the Justice Department provide facts to prove its allegations.
The agency said a 22-page letter that it sent Arpaio's office in December provides the facts of the allegations and that giving further information would delay the settlement.
The federal agency said an Arpaio lawyer acknowledged in earlier settlement talks that negotiations would go forward without the Justice Department providing additional information since that information would be necessary only as part of a lawsuit.
The agency also said in Tuesday's letter that it has found additional information to support its allegation that Arpaio's office failed to adequately investigate a large number of sex-crimes cases.
The Justice Department is seeking an agreement that would require the sheriff's office to train officers in how to make constitutional traffic stops, collect data on people arrested in traffic stops and reach out to Latinos to ensure them that the department is there to also protect them.
Earlier in the three-year investigation, the agency filed a 2010 lawsuit against the sheriff, alleging that his office refused to fully cooperate with a request for records and access to jails and employees. The case was settled last summer after the sheriff's office handed over records and gave access to employees and jails.
Fox News’ Mike Levine and the Associated Press contributed to this report.