WASHINGTON, April 10 (Reuters) - President Donald Trump's administration is pushing forward with plans to sell up to a dozen aircraft to Nigeria's air force for the fight against the extremist group Boko Haram, a congressional source said on Monday, a deal that could be worth up to $600 million.
The A-29 aircraft, with reconnaissance and surveillance as well as attack capabilities, are made by Brazil's Embraer . But they use U.S. parts and are assembled in Florida, so they are subject to U.S. export rules.
Former President Barack Obama's administration originally agreed on the sale, but it was put on hold after incidents including the Nigerian Air Force's bombing of a refugee camp in January that killed 90 to 170 civilians.
The Trump administration wants to push ahead with the sale to boost Nigeria's efforts to fight Boko Haram and to bolster hiring by defense firms in the United States.
"We've been told that the administration is going to go forward with that transaction," the congressional aide said.
Formal notification of the deal has not yet been sent to Congress but is expected shortly. Trump has said he plans to go ahead with foreign defense sales that had been held up under Obama due to human rights concerns.
In March, the administration informed Congress of its plans to pursue a $5 billion sale to Bahrain of Lockheed Martin F-16s and related equipment, which had been held up under Obama when Bahrain failed to meet human rights targets.
Reuters first reported the Obama administration's plan to sell the Embraer aircraft to Nigeria in May 2016, as a vote of confidence in President Muhammadu Buhari's drive to reform the country's military.
The Trump administration's plan to move ahead with the Nigerian sale was first reported on Monday by the Associated Press.
The congressional source said concerns remain about the sale, despite its receiving the backing of some lawmakers. One is lingering unease about the Nigerian military. Another is whether Nigeria's government will be able to pay the full $600 million for the aircraft, equipment, training and support.
This could affect the final size of the deal, the source said.
Senior U.S. officials said Buhari had long expressed frustration over delays in the decision to sell Nigeria the aircraft and raised it in a phone call with Trump in February. (Additional reporting by Lesley Wroughton and Mike Stone; editing by Cynthia Osterman)