A top EPA official has resigned after coming under scrutiny for 2010 remarks in which he compared the agency's enforcement strategy to Roman crucifixion.

Al Armendariz, the top environmental official in the oil-rich South and Southwest region, resigned in a letter to EPA Administrator Lisa Jackson on Sunday, saying he did not want to be a distraction for the agency. The resignation is effective Monday.

"As I have expressed publicly, and to you directly, I regret comments I made several years ago that do not in any way reflect my work as regional administrator. As importantly, they do not represent the work you have overseen as EPA administrator," he wrote. "I take great pride in having built a career based on integrity and hard work. These are the principles that guide me personally as well. While I feel there is much work that remains to be done for the people of this country in the region that I serve, after a great deal of thought and careful consideration, I have come to the conclusion that my continued service will distract you and the agency from its important work."

Armendariz made the original remarks at a local Texas government meeting in 2010. He relayed to the audience what he described as a "crude" analogy he once told his staff about his "philosophy of enforcement."

"It was kind of like how the Romans used to, you know, conquer villages in the Mediterranean," he said. "They'd go in to a little Turkish town somewhere, they'd find the first five guys they saw, and they'd crucify them.

"And then, you know, that town was really easy to manage for the next few years," he said.

Armendariz went on to say that "you make examples out of people who are, in this case, not complying with the law ... and you hit them as hard as you can" -- to act as a "deterrent" to others.

Republican lawmakers blasted him for the comments as Obama administration officials made clear the remarks did not represent the views of the EPA as a whole. Jackson said in a statement Monday that she accepted the resignation.

"I respect the difficult decision he made and his wish to avoid distracting from the important work of the agency," she said, thanking him for his service.

Republicans in Congress had called for Armendariz' firing, after Oklahoma Sen. James Inhofe highlighted the May 2010 speech last week as proof of what he refers to as EPA's assault on energy, particularly the technique of hydraulic fracturing, or fracking.

Several disputed contamination cases in Texas have helped stoke environmental concerns over fracking.

Inhofe said Monday that the resignation would not stop the ongoing investigation into EPA policies.

"We will continue our investigation into the situations surrounding EPA's apparent crucifixion victims: the American people deserve to know why, in at least three separate cases, EPA tarnished the reputation of companies by accusing them of water contamination; then when the results of their study did not turn out the way they hoped, and they had no definitive evidence to make that link, they quietly walked back their accusations. We will get to the bottom of this -- and we will continue looking into EPA's actions on hydraulic fracturing beyond these three cases as well," he said in a statement.

The Associated Press contributed to this report.