Elizabeth Warren. Ethan Miller/Getty Images Sen. Elizabeth Warren of Massachusetts promised on Thursday that she, along with four other Democratic senators, would introduce legislation to force President-elect Donald Trump to divest entirely from his business empire.

"Americans deserve to know that the president is doing what's best for the country — not using his office to do what's best for himself," she tweeted. "The only way for @realDonaldTrump to eliminate conflicts-of-interest is to divest his financial interests and place them in a blind trust."

The Massachusetts Democrat wrote that Sens. Ben Cardin of Maryland, Chris Coons of Delaware, Dick Durbin of Illinois, and Jeff Merkley of Oregon would introduce legislation next month seeking to define Trump's obligations under the Emoluments Clause, a passage in the Constitution that forbids government officials from receiving gifts from foreign governments.

As The Washington Post reported last month, a payment from a foreign official or state-owned company to a Trump hotel or other company bearing his name may violate the clause. So could favorable legislation or treatment overseas from a government aimed at benefiting a Trump property. But some have argued that the clause does not apply to the presidency.

After canceling a highly anticipated press conference set for Thursday on what he would do regarding his business empire, Trump announced in a series of tweets early this week that "even though I am not mandated by law to do so," he would leave his businesses before his inauguration.

"Two of my children, Don and Eric, plus executives, will manage them," he wrote. "No new deals will be done during my term(s) in office."

But a true blind trust, which Trump has touted as his plan along the campaign trail and in the weeks following his electoral victory, would not include involvement from one's family members; it would require an independent manager who is not closely tied to the holder.

In addition, Trump's two adult sons have reportedly been a part of the selection process for some Cabinet positions, and both sat in on a meeting between the president-elect and tech leaders Wednesday.

"Placing assets in a true blind trust has been the standard for previous presidents," Warren wrote Thursday. "Our bill makes clear we expect Trump to do the same."

Earlier this week, ethics experts expressed that the latest promises from Trump would, if enacted, still not be enough to clear up the conflicts of interest.

"The acid test for President-elect Donald Trump's conflicts of interest is: Will he sell the family business?" Robert Weissman, the president of the advocacy group Public Citizen, said in a statement, adding that Monday night's tweets suggested Trump would "not divest, which means that nothing of consequence has changed."

Weissman wrote that Trump would continue to have conflicts of interests stemming from his business operations, including those overseas, no matter who was running the Trump Organization so long as he still had a stake in it, adding that Trump would be able to financially benefit from policies as wide-ranging as consumer protection, taxes, labor rights, and bankruptcy.

"Candidate Trump promised to root out corruption, cronyism and insider dealmaking," he wrote. "President-elect Trump is making a mockery of those promises, starting with his refusal to end his own conflicts of interest, as serious as any in the history of the American presidency."