The Marine Corps is expected to ask to keep several front-line combat jobs closed to women, a senior military official told Fox News -- bucking the trend being followed by the other three military services.
The official said the Marine Corps would request a waiver to keep women excluded from infantry and artillery positions, but not armor positions like serving in tank units.
The Associated Press, citing U.S. officials, first reported Friday that the Corps' tentative decision has ignited tension between Navy and Marine leaders and raised a debate over whether Navy Secretary Ray Mabus can veto any Marine Corps proposal to prohibit women from serving in certain infantry and reconnaissance positions.
The AP reported that no final decision had been made or presented to Marine leaders, but officials say Defense Secretary Ash Carter is aware of the dispute and intends to review the Marine plan.
The report comes nine days after the Marines released a study that found that all-male infantry units performed at a higher-level than units with women in them. Specifically, the study found that the all-male units moved faster, shot more accurately, could carry more weight and suffered fewer injuries than gender-integrated units. The injuries suffered by female Marines included stress fractures that likely resulted from carrying heavy loads.
The report did acknowledge that "female Marines have performed superbly in the combat environments of Iraq and Afghanistan and are fully part of the fabric of a combat-hardened Marine Corps after the longest period of continuous combat operations in the Corps' history."
But the report also pointed to the 25-year-old report by a presidential commission on women in the armed forces that concluded: "Risking the lives of a military unit in combat to provide career opportunities or accommodate the personal desires or interests of an individual, or group of individuals, is more than bad military judgment. It is morally wrong."
The ongoing divide has put Marine Corps Commandant Gen. Joseph Dunford in the spotlight as he prepares to take over as Chairman of the Joint Chiefs of Staff next week. And it puts him in a somewhat awkward position of eventually having to review and pass judgment -- as chairman -- on a waiver request that he submitted himself while serving as Marine commandant.
Officials say the Army, Navy and Air Force are expected to allow women to serve in all combat jobs and will not ask Carter for any exceptions. They say that Special Operations Command is also likely to allow women to compete for the most demanding military commando jobs -- including the Navy SEALs -- though with the knowledge that it may be years before women even try to enter those fields.
Mabus on Monday made his position clear.
"I'm not going to ask for an exemption for the Marines, and it's not going to make them any less fighting effective," he said, adding that the Navy SEALs also will not seek any waivers. "I think they will be a stronger force because a more diverse force is a stronger force. And it will not make them any less lethal."
Mabus' comments angered Rep. Duncan Hunter, R-Calif., who has asked Carter in a letter to demand Mabus' resignation because he "openly disrespected the Marine Corps as an institution, and he insulted the competency of Marines by disregarding their professional judgment, their combat experience and their quality of leadership."
Hunter, who served as a Marine in Iraq and Afghanistan, said Mabus' comments raise questions about whether he can be objective and continue to lead the Marine Corps. And he said Mabus should have no role in any decisions about women in the Marine Corps.
Mabus, however, told the City Club of Cleveland that the Marine study relied on averages -- such as the average woman can't carry as much or perform as quickly as a man.
"The other way to look at it is we're not looking for average," said Mabus. "There were women that met this standard, and a lot of the things there that women fell a little short in can be remedied by two things: training and leadership."
Under the current plan, the service chiefs will present their plans to the service secretaries, who will then forward recommendations to Carter. He will make the final decisions by the end of the year.
If Dunford does seek the exception, it puts the new Joint Chiefs chairman at odds with public statements by Carter asserting that anyone, regardless of gender, who meets the standards and requirements for a job should be allowed to do it.
Women make up less than 8 percent of the Marine Corps, the smallest percentage across the four active-duty services.
The services have been slowly integrating women into previously male-only roles, including as Army artillery officers and sailors on Navy submarines. Adding to the debate was the groundbreaking graduation last month of two women in the Army's grueling Ranger course.
In January 2013, then-Defense Secretary Leon Panetta and Joint Chiefs Chairman Gen. Martin Dempsey signed an order wiping away generations of limits on women fighting for their country, ordering a quarter-million positions open regardless of gender. They called for sweeping reviews of the physical requirements for combat jobs and gave the military services until January 2016 to argue if any positions should remain closed to women.
Fox News' Lucas Tomlinson and The Associated Press contributed to this report.