Donald Trump hid losses of more than $70m at his eponymous Washington DC hotel while he was in the White House, House Democrats said on Friday.

The House oversight committee said the deception was detailed in documents released by the General Services Administration (GSA), which leased the Old Post Office building on Pennsylvania Avenue to the Trump Organization in 2011 and which signed off on its operation of the hotel after Trump entered the White House, just steps away.

Trump has faced wide-ranging questions about alleged self-dealing to his businesses while he was in power.

His Washington hotel became a place for Republicans to be seen and to do business but it suffered under the pandemic and after Trump’s defeat by Joe Biden last November. The Trump Organization is reported to be nearing a sale of the lease.

According to the House committee: “On his federally mandated financial disclosures, President Trump reported that the Trump Hotel earned him over $150m in revenue during his time in office.

“However, the records obtained by the committee show that the Trump Hotel actually incurred net losses of over $70m, leading the former president’s holding company to inject at least $24m to aid the struggling hotel.

“By filing these misleading public disclosures, President Trump grossly exaggerated the financial health of the Trump Hotel. He also appears to have concealed potential conflicts of interest stemming not just from his ownership of this failing business but also from his roles as the hotel’s lender and the guarantor of its third-party loans.”

The committee said that in 2018 Trump received preferential treatment from Deutsche Bank, which allowed him to delay payments on a $170m loan.

“Without this deferral,” the committee said, “the hotel may have needed to pay tens of millions of additional dollars to Deutsche Bank at a time when it was already facing steep losses. Mr Trump did not publicly disclose this significant benefit from a foreign bank while he was president.”

Links between Trump, figures close to him and Deutsche Bank have been scrutinised during investigations of Russian election interference, throughout Trump’s presidency and in its aftermath.

The committee said the bank allowed Trump to defer payments for six years. By that time he would have been out of office even had he beaten Biden in 2020 and any default would perhaps have been less politically damaging.

The committee also said Trump failed to reveal sufficient details of more than $3.7m received from foreign governments, “sufficient to cover over 7,400 nights at the Trump Hotel at the average daily rate” and potentially violating the emoluments clause of the US constitution, which is meant to stop federal officials profiting from their positions.

Trump also concealed debts when he obtained the lease on the Old Post Office from the GSA in 2011, then “transferred millions of dollars in and out of his DC Hotel through affiliated entities and opaque transactions”, the committee said.

The committee chair, Carolyn Maloney of New York, and Gerald Connolly of Virginia, chairman of the subcommittee on government operations, wrote to the head of the GSA.

The documents “raise new and troubling questions about former president Trump’s lease with GSA,” they said, “and the agency’s ability to manage the former president’s conflicts of interest during his term in office when he was effectively on both sides of the contract, as landlord and tenant.

“… This new evidence raises many questions that require further investigation and action by the committee.”

Trump and the Trump Organization did not immediately comment. Trump has said investigations of his financial affairs are politically motivated and without legal merit.

The news comes at a troubled time for Trump and his business interests. This week, for the first time, he was not included in Forbes’ list of the richest 400 Americans.

“If Trump is looking for someone to blame, he can start with himself,” said Forbes.