Congress is expected to receive formal notification within weeks, setting in motion a deal with Nigeria that the Obama administration had planned to approve at the very end of Barack Obama’s presidency. The arrangement will call for Nigeria to purchase up to 12 Embraer A-29 Super Tucano aircraft with sophisticated targeting gear for nearly $600 million, one of the officials said.

The officials were not authorized to discuss the terms of the sale publicly and requested anonymity to speak about internal diplomatic conversations.

An Embraer spokeswoman declined to comment on the deal.

Though President Donald Trump has made clear his intention to approve the sale of the aircraft, the National Security Council is still working on the issue. Military sales to several other countries are also expected to be approved but are caught up in an ongoing White House review. Nigeria has been trying to buy the aircraft since 2015.

The Nigerian air force has been accused of bombing civilian targets at least three times in recent years. In the worst incident, a fighter jet on Jan. 17 repeatedly bombed a camp at Rann, near the border with Cameroon, where civilians had fled from Boko Haram. Between 100 and 236 civilians and aid workers were killed, according to official and community leaders’ counts.

That bombing occurred on the same day the Obama administration intended to officially notify Congress the sale would go forward. Instead, it was abruptly put on hold, according to an individual who worked on the issue during Obama’s presidency. Days later, Trump was inaugurated.

Sen. Bob Corker, R-Tenn., the chairman of the Foreign Relations Committee, said this past week that he supported the A-29 deal to Nigeria as well as the sale of U.S.-made fighter jets to Bahrain that had been stripped of human rights caveats imposed by the Obama administration.

Under Obama, the U.S. said Bahrain failed to make promised political and human rights reforms after its Sunni-ruled government crushed Arab Spring protests five years ago.

“We need to deal with human rights issues, but not on weapons sales,” Corker said.

The State Department said in a 2016 report that the Nigerian government has taken “few steps to investigate or prosecute officials who committed violations, whether in the security forces or elsewhere in the government, and impunity remained widespread at all levels of government.”

Amnesty International has accused Nigeria’s military of war crimes and crimes against humanity in the extrajudicial killings of an estimated 8,000 Boko Haram suspects. President Muhammadu Buhari promised to investigate the alleged abuses after he won office in March 2015, but no soldier has been prosecuted and thousands of people remain in illegal military detention. Nigeria’s military has denied the allegations.

The A-29 sale could improve the U.S. relationship with Nigeria, Africa’s largest consumer market of 170 million people, the continent’s biggest economy and its second-largest oil producer.

The aircraft deal also would satisfy Trump’s priorities to support nations fighting Islamic uprisings, boost U.S. manufacturing and create high-wage jobs at home. The A-29 aircraft, which allow pilots to pinpoint targets at night, are assembled in Jacksonville, Florida.

Embraer is a Brazilian conglomerate, but the company has been in the United States for nearly 40 years, a spokeswoman said. The company also operates facilities in California, Tennessee, Arizona and Connecticut, employing nearly 2,000 people.

Once Congress is officially notified of the sale, lawmakers who want to derail it have 30 days to pass veto-proof legislation. Sen. John McCain, R-Ariz., chairman of the Armed Services Committee, also said he backs the sale.

“We’ve really got to try to do what we can to contain them,” McCain said of Boko Haram.

A Feb. 15 White House statement summarizing Trump’s first phone call with Buhari said the president “expressed support for the sale of aircraft from the United States to support Nigeria’s fight against Boko Haram.”

Sen. Ben Cardin of Maryland, the top Democrat on the Foreign Relations Committee, said in mid-February he was “leery” of the sale because of the Nigerian military’s impunity. Cardin said this week he’s not trying to block the deal.

“Ultimately we hope that the sale goes forward,” he said. “But there is progress that needs to be made in protecting the civilian population.”