Attorney General Terry Goddard said he urged them not to sue. "I told them we need solutions from Washington, not more lawsuits," the Democrat said.
The Justice Department initiated separate meetings by phone and face-to-face in Phoenix with Goddard and aides to Republican Gov. Jan Brewer to reach out to Arizona's leaders and elicit information from state officials regarding the Obama administration's concerns about the new law.
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The strong message that the Justice Department representatives delivered at the private meetings - first with Goddard, then with Brewer's staff - left little doubt that the Obama administration is prepared to go to court if necessary in a bid to block the new law, which takes effect July 29.
Goddard said he noted that five privately filed lawsuits already are pending in federal court to challenge the law.
"Every possible argument is being briefed," Goddard said.
Key provisions of the sweeping law include a requirement that police enforcing any other law question people about their immigration status if there is "reasonable suspicion" that the people are in the country illegally. It also makes it a state crime to be in the country illegally.
Arizona has an estimated 460,000 illegal immigrants, and the law's supporters contend it will save taxpayer money and reduce crime by pressuring illegal immigrants to "self-deport."
Federal officials and other critics fear the state law could lead to widespread racial profiling.
Goddard said it would be wrong to assume that Arizona law enforcement officers would not act in a fair and highly professional manner."
Goddard vowed to defend the law in court.
"While Senate Bill 1070 is far from perfect, it is a response to a very serious problem," Goddard said. "I told the lawyers that it would be just plain wrong for the federal government to sue to stop Arizona from dealing with something that the federal government has ignored for so many years."
Brewer's office declined immediate comment.
The federal officials' trip to Phoenix also was an effort to see if the two sides can find common ground in the debate, which has reignited immigration as a major political issue nationwide.
A number of other states are considering laws similar to Arizona's.
Justice Department spokesman Matthew Miller noted that U.S. Attorney General Eric Holder met with a number of police chiefs Wednesday in Washington "to hear their concerns about the impact of the Arizona law on their ability to keep communities safe.
"We continue to have concerns that the law drives a wedge between law enforcement and the communities they serve and are examining it to see what options are available to the federal government," Miller said.
While numerous police chiefs have criticized the law, several Arizona associations representing rank-and-file police officers support it.