Donald J. Trump’s businesses received at least $7.8 million from 20 foreign governments during his presidency, according to new documents released by House Democrats on Thursday that show how much he received from overseas transactions while he was in the White House, most of it from China.

The transactions, detailed in a 156-page report called “White House For Sale” that was produced by Democrats on the House Oversight Committee, offer concrete evidence that the former president engaged in the kind of conduct that House Republicans have labored, so far unsuccessfully, to prove that President Biden did as they work to build an impeachment case against him.

Using documents produced through a court fight, the report describes how foreign governments and their controlled entities, including a top U.S. adversary, interacted with Trump businesses while he was president. They paid millions to the Trump International Hotel in Washington, D.C.; Trump International Hotel in Las Vegas; Trump Tower on Fifth Avenue in New York; and Trump World Tower at 845 United Nations Plaza in New York.

House Democrats highlighted the transactions on Thursday as a counterweight to Republicans’ impeachment inquiry into Mr. Biden, which has sought to tie him to international business deals by his son Hunter Biden before his father became president in a bid to prove corruption or influence peddling. They have so far failed to show that President Biden was enriched in any way by any of those transactions.

”By elevating his personal financial interests and the policy priorities of corrupt foreign powers over the American public interest, former President Trump violated both the clear commands of the Constitution and the careful precedent set and observed by every previous commander in chief,” Representative Jamie Raskin of Maryland, the top Democrat on the Oversight Committee, wrote in a foreword to the report.

Among the countries patronizing Mr. Trump’s properties, China made the largest total payment — $5.5 million — to his business interests, the report found. Those payments included millions of dollars from China’s Embassy in the United States, the Industrial and Commercial Bank of China and the Hainan Airlines Holding Company.

Saudi Arabia was the second-largest spender, shelling out more than $615,000 at the Trump World Tower and Trump International Hotel.

Eric Trump, the former president’s son, has long insisted that foreign interests did not influence his father’s presidency and that any profit the company earned on the hotel stays was returned to the federal government through a voluntary annual payment to the Treasury Department.

The Constitution prohibits a president from accepting money, payments or gifts “of any kind whatever” from foreign governments and monarchs unless he obtains “the consent of the Congress” to do so. The report notes that Mr. Trump never went to Congress to seek consent.

The report also acknowledges its own limitations. Democrats fought aggressively through years of litigation to gain access to only a portion of Mr. Trump’s business records. After they won court rulings, Mazars USA, the longtime accounting firm for Mr. Trump that cut ties with him and his family business, began in 2022 turning over documents related to his financial dealings.

The development came after Mazars said it could no longer stand behind a decade of annual financial statements it had prepared for the Trump Organization.

But once Republicans won control of Congress, they dropped the effort to force Mazars to continue with its production of documents about Mr. Trump’s business dealings.

Representative James R. Comer, Republican of Kentucky and the chairman of the Oversight Committee, made clear he had abandoned any investigation into the former president’s financial dealings and was instead focusing on whether Mr. Biden and members of his family were involved in an influence-peddling scheme.

Still, Democrats say they received key material before the investigation was shut down.

“Critically, even this subset of documents reveals a stunning web of millions of dollars in payments made by foreign governments and their agents directly to Trump-owned businesses while President Trump was in the White House,” the report states. “These payments were made while these governments were promoting specific foreign policy goals with the Trump administration and even, at times, with President Trump himself, and as they were requesting specific actions from the United States to advance their own national policy objectives.”

The report is the result of a multiyear investigation into Mr. Trump’s receipt of payments from foreign-controlled entities while in office. The investigation began in 2016 under the leadership of Representative Elijah E. Cummings, Democrat of Maryland, who died in 2019.

It noted that Mr. Trump sometimes bragged about the wealth that foreign governments had provided him, including at a campaign rally in 2015, when he suggested that his personal financial incentives might influence his dealings with another government.

“Saudi Arabia, I get along great with all of them.,” the report quotes him saying. “They buy apartments from me. They spend $40 million, $50 million. Am I supposed to dislike them? I like them very much!”

The report urges Congress to consider adopting new disclosure rules to help the legislative branch obtain information for proper oversight. It also recommends a more formal procedure for presidents and other officials to seek Congress’s permission when they receive and want to retain wealth from other countries.