WASHINGTON >> The White House has yet to approve a Pentagon request to provide imminent-danger pay to U.S. troops assigned to Niger, a top military commander said today, raising new questions about the support given to service members who are sent to West Africa to help in the fight against terrorist groups.

Gen. Thomas D. Waldhauser told House lawmakers that the U.S. Africa Command, which he heads, had some time ago “submitted a packet for Niger to qualify” for the additional pay in combat zones. He said the decision rested with the White House Office of Management and Budget, adding that “it’s at the national level now for final approval.”

Waldhauser’s remarks came during two hours of testimony before the House Armed Services Committee. He declined to answer questions about the military’s monthslong investigation into the death of four American soldiers and five Nigeriens, including an interpreter, in an Oct. 4 ambush in a remote stretch of desert scrub near Niger’s border with Mali.

The investigation, he said, is complete and with Defense Secretary Jim Mattis, who is going through it. Once Mattis signs off, Waldhauser said, military officials will brief the families of the four soldiers who were killed: Staff Sgt. Bryan C. Black, Staff Sgt. Dustin M. Wright, Staff Sgt. Jeremiah W. Johnson and Sgt. La David T. Johnson.

Not until the families are informed, Waldhauser said, will he and other military leaders brief Congress on the findings of the investigation.

Dozens of interviews conducted by The New York Times with current and former officials, soldiers who survived the ambush and villagers who witnessed it, point to a series of intelligence failures and strategic miscalculations that left the U.S. soldiers far from base, in hostile territory longer than planned, with no backup or air support and on a mission they had not expected to perform.

The team, initially assigned a routine patrol to meet with community leaders, was diverted by new orders to provide backup for another mission aimed at targeting a terrorist leader believed to be involved in the kidnapping of an American.

It remains unclear who gave the order for the new mission. Officers who have served in the region say such a change would have required approval from several higher levels — most likely starting with a major in Niamey, Niger’s capital, and a lieutenant colonel in Chad; a task force commander stationed in Germany; and possibly a two-star general overseeing all special forces operations in Africa, also from Germany, where the Africa Command is based.

Several Defense Department officials have said the delay in presenting the investigation’s findings was aimed in part at preventing lawmakers from focusing on the Niger ambush during Waldhauser’s scheduled testimony. In an email, Col. Mark Cheadle, a spokesman for the Africa Command, denied that assertion as “absolutely not true.”

Calling the investigation “exhaustive,” Waldhauser told the House committee that “we are prepared, once the families have been briefed, to brief you in a closed session.”

It was unclear what the Defense Department planned to tell the public about the report’s findings. Officials say they have been preparing both classified and unclassified versions of the report.