WASHINGTON (Reuters) - Former Senate Democrats have renewed a request to President Donald Trump and his firm to disclose the financial relationship with Saudi Arabia after the Washington Post reported that Riyadh had spent thousands of dollars on its foundation.

Democrats said, according to Senator Ed Markey, that the newspaper's investigation might explain why Trump's administration has cut off steps to protect Saudi Crown Prince Mohammed bin Salman, whose CIA role in the killing of journalist Jamal Khashoggi has been confirmed.

Democrats said Trump's refusal to take responsibility for Khashoggi's killing of Saudi Arabia was "a disgrace to our values ​​as a nation."

The Washington Post published an investigation into the Saudi government spending hundreds of thousands of dollars to book 500 rooms at the Trump Hotel through US lobbying groups, about a month after Trump won the 2016 presidential election.

In details of the investigation, Saudi-funded lobbyists spent more than $ 270,000 to accommodate six visiting visitor groups at the Trump Hotel, which is still owned by the US president.

The bookings resulted in two cases being brought before the federal court for Trump's violation of the constitution for illegally receiving funds from foreign governments.

The Democrats sent a previous letter last October to the Trump administration demanding financial and business ties between Saudi Arabia and the Trump family.

According to the letter, government reports indicate that the Trump Foundation has entered into commercial agreements with members of the royal family for decades, including the acquisition of a Saudi prince at the Plaza Hotel in a deal worth 325 million dollars after the repayment of the Trump Corporation.

The letter added that Trump's recent comments, along with government reports of increased Saudi government spending on Trump's property, were a major concern over financial conflicts of interest.