Just two days before the 9/11 anniversary attack on the U.S. consulate in Benghazi, two leaders of the Libyan militias responsible for keeping order in the city threatened to withdraw their men.

The brinksmanship is detailed in a cable approved by Ambassador Chris Stevens and sent on the day he died in the attack, the worst assault on a U.S. diplomatic mission since the 1979 hostage crisis in Iran. The dispatch, which was marked “sensitive” but not “classified,” contained a number of other updates on the chaotic situation on the ground in post-Gaddafi Libya.

The cable, reviewed by The Daily Beast, recounts how the two militia leaders, Wissam bin Ahmed and Muhammad al-Gharabi, accused the United States of supporting Mahmoud Jibril, the head of the Libyan transitional government, to be the country’s first elected prime minister. Jibril’s centrist National Forces Alliance won the popular vote in Libyan elections in July, but he lost the prime minister vote in the country’s Parliament on Sept. 12 by 94 to 92. Had he won, bin Ahmed and al-Gharabi warned they “would not continue to guarantee security in Benghazi, a critical function they asserted they were currently providing,” the cable reads. The man who beat Jibril, Mustafa Abushagur, lost a vote of no-confidence Sunday, throwing Libyan politics back into further uncertainty.

The threat from the militias underscores the dangers of relying on local Libyan forces for security in the run-up to the 9/11 military-style assault. The U.S. consulate in Benghazi employed a militia called the “February 17 Martyrs Brigade” for security of the four-building compound. In addition, there were five Americans serving as diplomatic security and a group of former special operations forces that acted as a quick reaction force on the day of the 9/11 attack. Members of the militias led by bin-Ahmed and al-Gharabi overlapped with the February 17 militia, the cable says.

Jason Chaffetz, the Republican lawmaker who has led the House Oversight and Government Reform committee’s investigation into the 9/11 attack, says the State Department actually decreased U.S. diplomatic security personnel in the months leading up to the attack.

The cable, titled “Benghazi Weekly Report – September 11, 2012,” notes the dangerous environment in eastern Libya. It does not, however, make a specific plea to Washington for more personnel or more security upgrades, and concludes that much of the violence in the country consists of Libyans attacking other Libyans, as opposed to specific plots directed at the West. Indeed, it says that in a meeting with Stevens, members of the Benghazi Local Council said security in their city was improving.

At the same time, the cable makes no mention of the anti-Muslim YouTube video or planned protests at the consulate, two key pillars of the Obama administration’s initial narrative on the 9/11 attacks.

Chaffetz, who visited Tripoli on Saturday, told The Daily Beast he has obtained documents and conducted interviews with whistle blowers that show the U.S. mission Libya did request more security from Washington in the run-up to the attack, but was denied. “Regional security officers were denied requests for more personnel and security upgrades to the four buildings and the perimeter security of the U.S. mission in Benghazi,” he told The Daily Beast on Sunday. More details on that negotiation will likely come out on Wednesday, when Chaffetz will hold his committee’s first hearing on the Benghazi attack.

The cable in some ways is bittersweet. It provides a snapshot of U.S. activities in Libya’s second-largest city before the assault that killed Stevens and three other Americans. It acknowledged the rise of Islamist forces in the militias and in the nearby city of Dernaa, a hotbed of al Qaeda recruiting in the last decade. In that city, an outfit called the “Abu-Salim Brigade” was beginning to enforce a harsh version of Islamic law that prohibited any co-mingling of men and women at the local university. One correspondent with the late ambassador urged him to send someone to Dernaa to “see the truth for yourselves.”

But the cable also details how the U.S. mission in Libya was optimistic about Libya’s future. The cable described plans for something called “the American space” in Benghazi. The new facility would contain “a small library, computer lab, and open space for programming.” It said the new facility has already been used for a dialogue on foreign policy with young Libyans.