Six out of the 12 Super Tucano fighter jets purchased from the U.S government in April, 2018 arrived Nigeria 7 days ago.

The lawmakers, top Democrats and Republicans on the Senate Foreign Relations Committee have reportedly delayed clearing a proposed sale of 12 AH-1 Cobra attack helicopters and accompanying defence systems to the Nigerian military.

The deal is worth $875 million, according to US officials and congressional aides familiar with the matter.

Other equipment are the proposed sale of the 28 helicopter engines produced by GE Aviation, 14 military-grade aircraft navigation systems made by Honeywell, and 2,000 advanced precision kill weapon systems—laser-guided rocket munitions, according to information sent by the State Department to Congress and reviewed by Foreign Policy magazine.

The behind-the-scenes controversy over the proposed arms sale illustrates a broader debate among Washington policymakers over how to balance national security with human rights objectives.

The hold on the sale also showcases how powerful U.S. lawmakers want to push the Biden administration to rethink U.S. relations with Nigeria amid concerns that President Buhari is drifting toward authoritarianism as his government is besieged by multiple security challenges, including a jihadist insurgency.

Chairperson of the Senate Foreign Relations Committee, Sen. Bob Menendez, called for a “fundamental rethink of the framework of our overall engagement” with Nigeria during a Senate hearing with US Secretary of State, Antony Blinken in June.