The United States has shipped about 40 tons of small arms and munitions to Somalia in the last two months to help the country’s transitional government fight off a challenge from Islamist militants, a senior American official has revealed.

The value of the military aid totals less than U.S. $10 million, the official said, and it comprises weapons for use “in an urban environment, fighting a counter-guerilla insurgency.”

The unnamed official revealed limited details of U.S. military assistance at a briefing of journalists at the U.S. State Department in Washington, DC on Friday. The briefing was arranged after the State Department’s spokesman confirmed on Thursday that the U.S. is providing arms and ammunition to the Transitional Federal Government (TFG).

The transcript of the briefing published by the department described the briefer only as a “senior State Department official.” Reporters present wrote that the briefing was held under ground rules requiring that the official remain anonymous.

The official told journalists that the military assistance was being provided through Ugandan and Burundian peacekeeping forces.

“We’re essentially doing two things,” he said. “We have provided funds for the purchase of weapons; and we have also asked the two units that are there, particularly the Ugandans, to provide weapons to the TFG, and we have backfilled the Ugandans for what they have provided to the TFG government.”

Pressed on what the aid was worth, the official said “at this point, it’s certainly under $10 million.” It had “substantially increased” since the beginning of the assault on the TFG launched by the al-Shabaab militia early in May.

“The extension of funding directly to the TFG is consistent with our efforts and support to help the TFG as much as possible to gain stability in the region,” the official said.