U.S. President Donald Trump said on Wednesday he expected Saudi Arabia and Russia to reach a deal in the next few days on oil production to end a price war that has "ravaged" the oil industry worldwide.

"I think that Russia and Saudi Arabia at some point are going to make a deal, in the not-too-distant future, because it's very bad for Russia, it's very bad for Saudi Arabia," Trump said at a White House news conference, adding he had separate "great" conversations with Saudi Crown Prince Mohammed bin Salman and Russian President Vladimir Putin in recent days.

Trump's national security adviser Robert O'Brien also said the U.S. "will work with the world's largest oil producers to address volatility in global oil markets."