US President Donald Trump's proposal to hire a US oil company to run oil fields in Syria has drawn criticism from legal and energy experts.

"This is not only a dubious legal step, but also sends a message to the whole region and the world that America wants to steal oil," said Bruce Riedel, a former adviser to the White House National Security Council and a researcher at the Brookings Institution.

On Sunday, Trump announced at a news conference that ISIS leader Abu Bakr al-Baghdadi had been killed in an operation by US special forces and talked about oil in Syria. And do it properly ... and distribute wealth. "

"International law seeks to protect against this kind of exploitation," said Laurie Blanc, a professor at Emory Law School and director of the Center for International and Comparative Law.

"The idea that the United States will keep oil in the hands of ExxonMobil or another unethical and possibly illegal US company," said Jeff Colgan, professor of political science and international studies at Brown University. He said US companies would face a "set of practical challenges" to operate in Syria.

Syria was producing about 380,000 barrels of oil a day before the war. A 2016 IMF working paper estimated production fell to only 40,000.

Ellen Roald, a researcher at the Atlantic Council's World Energy Center (a forum for researchers and opinion leaders), said just trying to develop Exxon or another major oil company would be "a difficult process" given Syria's relatively limited infrastructure and scant production.

Alex Cranberg, president of Aspect Energy Holdings, who has been exploring oil in the Kurdistan region of Iraq, says the United States should take care of the fate of Syria's oil fields.

"The idea is not that oil itself matters to the United States a lot, but its misuse could fund future problems for us ... if it falls into the wrong hands," he said. He noted that the White House had not reached out to his company about the proposal.

"US control of the fields and the hard currency they provide will be a major influence on Syria's future," Cranberg said.