Chad threatened to end the Status of Forces Agreement (SOFA) with the United States, which governs how US military forces can operate in the country, the report said, citing four US sources.
The letter ordered the United States to remove personnel from the French base in N’Djamena, although it did not explicitly demand the US military to leave Chad.
Chad specifically raised the presence of a US Special Operations Task Force at the base, but all US military personnel in Chad are located in N’Djamena.
A US official reportedly said that there are fewer than 100 US troops in Chad. While Chad did not send the letter through official diplomatic channels, that could be a negotiating tactic by N'Djamena to secure a better agreement.
The threat to end the agreement caught US officials off guard as Chad could be attempting to replicate the actions of Niger, which ended its agreement with the US military last month, according to the report.