An Arizona sheriff said he planned to defy Washington’s attempts to roll back his staunch enforcement of federal immigration law, a move that could put him on a collision course with the U.S. government.

Late last year, U.S. Immigration and Customs Enforcement, the largest arm of the Department of Homeland Security, stripped Maricopa County Sheriff Joe Arpaio of the authority to use 100 of his deputies to enforce federal immigration in his jurisdiction, which includes Phoenix. The customs agency took the action because Mr. Arpaio’s aggressive immigration crackdowns had drawn criticism from human-rights groups and had run afoul of the U.S. Justice Department, which is investigating whether he has used racial profiling and abused his authority.

In an interview this week, Mr. Arpaio said he would ignore Washington’s effort to clip his powers and would train all of his 881 deputies to enforce federal immigration law on the streets.

“We have the inherent right to enforce federal immigration law,” Mr. Arpaio said. “If Washington doesn’t like it, I recommend they change the laws.”

Asked about Mr. Arpaio’s plans for reinstating street-level immigration enforcement, an ICE spokesman in Arizona said: “Sheriff Arpaio’s efforts to conduct immigration-enforcement actions do not derive from any ICE-delegated federal authority.”

The dispute stems from a provision called 287g, a federal program that enlists and trains local police to identify suspected illegal-immigrant criminals in jails and on the streets. The program was intended to target serious criminals. However, it was criticized for promoting racial profiling and serving as an excuse for local law-enforcement officers to hunt down illegal immigrants. Mr. Arpaio gained notoriety for his tactics.

The Obama administration sought to rein in the 287g program as part of a broader effort to retool the ICE, which became known in recent years for raiding companies and rounding up illegal workers. The administration has been taking steps to tone down the agency’s image as a hard-edged enforcer.

When it attempted to curtail Mr. Arpaio’s authority, Washington limited his deputies’ ability to verify the immigration status of people in the streets during the course of duty. The deputies still retain the authority to check the status of people booked into Maricopa County jails.

“Since the Department of Homeland Security took away 100 of our federally trained deputies…we are going to train every sworn deputy to teach them how to enforce state and federal immigration laws,” the sheriff said in a telephone interview.

The course, which will mainly be taught via computer, will equip deputy sheriffs to “recognize…immigration violations” in the course of duty, Mr. Arpaio said.

Mr. Arpaio has partnered with Kris Kobach, a law professor who has gained prominence as a national advocate for stricter measures against illegal immigrants.

Mr. Arpaio said “we don’t engage in racial profiling.” He noted that the training for his deputies would include a lesson on how to avoid the practice.