The tentative decision has ignited 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. And it puts Gen. Joseph Dunford, the Marine Corps commandant who takes over soon as chairman of the Joint Chiefs of Staff, at odds with the other three military services, who are expected to open all of their combat jobs to women.
No final decisions have been made or forwarded to Pentagon leaders, but officials say Defense Secretary Ash Carter is aware of the dispute and intends to review the Marine plan. The Marine Corps is part of the Navy, so Mabus is secretary of both services.
The ongoing divide has put Dunford in the spotlight as he prepares to start his new job 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.
The debate includes jabs at Mabus for his public criticism of the Marine plan that triggered a call for his resignation from a member of Congress.
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.
The officials spoke on condition of anonymity because they weren't authorized to discuss the matter publicly.
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.
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.
Informing Dunford's decision is the Marine Corps' yearlong study on gender integration. It concluded that, overall, male-only units performed better than gender-integrated units. It found that the male-only infantry units shot more accurately, could carry more weight and move more quickly through specific tactical movements. It also concluded that women had higher injury rates than men, including stress fractures that likely resulted from carrying heavy loads.
The report acknowledged 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."
Women make up less than 8 percent of the Marine Corps, the smallest percentage across the four active-duty services.
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."
Mabus, however, told the City Club of Cleveland that while the Marines did a long study of the matter, it 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."
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.