President Donald Trump reportedly pushed Treasury Secretary Steven Mnuchin to label China a "currency manipulator," a move the secretary had resisted, The Washington Post reports.

According to the Post, Trump increased pressure on Mnuchin because he believes China intentionally allowed the yuan to weaken against the dollar. Anonymous sources told the Post that Mnuchin was reluctant to make the move, and his department declined to label China a currency manipulator in May, but Treasury made the designation official Aug. 5.

"Secretary Mnuchin, under the auspices of President Trump, has today determined that China is a Currency Manipulator," Treasury said in a statement.

"In recent days, China has taken concrete steps to devalue its currency, while maintaining substantial foreign exchange reserves, despite active use of such tools in the past," the statement continued. "The context of these actions and the implausibility of China's market stability rationale confirm that the purpose of China's currency devaluation is to gain an unfair competitive advantage in international trade."

One unnamed person close to Mnuchin said the point of the designation was to get China to return to trade negotiations, and that this has so far been unsuccessful.

Spokespeople from the Treasury and the White House declined to comment to the Post.

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