WASHINGTON: A group of US senators on Friday urged the government’s markets watchdog to investigate whether President Donald Trump or White House insiders broke securities laws ahead of his dramatic reversal on global tariffs.

The six Democrats -- led by Massachusetts progressive Elizabeth Warren -- noted in a letter to the Securities and Exchange Commission (SEC) that Trump posted on his website Truth Social early Wednesday that “THIS IS A GREAT TIME TO BUY!!!” as stock markets were tanking.

A few hours later, Trump announced a 90-day suspension of additional tariffs against dozens of countries, triggering a historic stock market rebound and the best day for the S&P 500 since the recovery from the 2008 financial crisis.

“We urge the SEC to investigate whether the tariff announcements... enriched administration insiders and friends at the expense of the American public,“ senators wrote in a letter to regulators at the Securities and Exchange Commission.

The letter urged the SEC to probe whether “any insiders, including the president’s family, had prior knowledge of the tariff pause that they abused to make stock trades ahead of the president’s announcement.”

Trump signed his Truth Social post with the letters “DJT” -- both his initials and the stock market abbreviation for his media company, Trump Media & Technology Group.

The company’s shares closed up 21.67 percent on Wednesday.

The senators called on the SEC to investigate whether the president, his donors or other insiders had engaged in market manipulation, insider trading or other violations of securities laws.

SEC chairman Paul Atkins has history with Warren, the top Democrat on the Senate Banking Committee, who has accused him of having conflicts of interest over his ties to the financial services industry.

Atkins is not obliged to do what the senators ask, and four of the group followed up with a second letter to the National Association of Attorneys General asking for state-level investigations.

“Corruption and lawlessness have become a calling card of the Trump administration,“ said Senate Minority Leader Chuck Schumer, one of the signatories of both letters.

The demand for action came amid concern over the growing number of avenues through which Trump and his family can monetize the power of the presidency, although no evidence of corruption had emerged.

Days before his inauguration, Trump released a “memecoin” -- a digital cryptocurrency token with no inherent value -- opening the door for secret donations from foreign buyers.

“Now anyone in world can essentially deposit money into bank account of President of USA with a couple clicks,“ his former aide Anthony Scaramucci posted on social media after the launch.

“Every favor -- geopolitical, corporate or personal -- is now on sale, right out in the open.”

The White House told The Washington Post that Trump’s Truth Social post sought only to “reassure” the public and that he had a responsibility to “reassure markets and Americans about their economic security.”