During an appearance at the Treasury Department,
Although the regulations were designed to end the problem of too-big-to-fail banks,
"These regulations enshrine too-big-to-fail and encourage risky behavior," Trump said.
Trump also signed an executive order directing Treasury Secretary
That review will include rules enacted by the Obama administration to crack down on so-called inversions in which companies shift their headquarters abroad to reduce their U.S. tax bills, Mnuchin told reporters Friday.
But while inversions are "one of the significant things" to be looked at, the review will be broad, he said.
"I think everyone would agree the tax system is way too complicated and burdensome," Mnuchin said.
Trump also said he would have a "big announcement" on tax reform on Wednesday. He provided no details during his Treasury appearance, but earlier Friday told the Associated Press that his proposal would contain "a massive tax cut" for businesses and individuals.
Like other Trump executive actions, Friday's orders simply direct Cabinet-level reviews and don't make any substantive changes in federal policy. In the case of Dodd-Frank, Trump already ordered the Treasury Department in early February to consult with regulators on a review of the entire law and report back in four months.
"The purpose of the orders is to make clear what the president's and the administration's priorities are and to signify the importance of these issues to the American people," Mnuchin told reporters Friday .
Trump is turning his attention to financial reform again as a top House Republican this week unveiled the latest version of legislation to replace Dodd-Frank, which was enacted in the wake of the financial crisis.
One of President Obama's signature accomplishments, Dodd-Frank was enacted with almost no Republican support. GOP lawmakers have criticized it as too heavy-handed and have sought major changes.
The legislation toughened bank regulations, sought to avoid future bailouts by creating a process to shut down teetering financial giants, established a powerful panel of regulators to watch for signs of instability and created the
"Any actions to undermine these protections encourage Wall Street's risky behavior and leave taxpayers and our economy exposed to another catastrophe," Brown said.
On Friday, Trump made the short walk from the White House to the Treasury Department for the first time since taking office to sign executive memos targeting two specific provisions about which Republicans have complained.
The first memo directs Mnuchin to review the law's orderly-liquidation authority and determine whether making changes to bankruptcy law "would be a superior alternative to resolve failing financial companies."
A key trigger to the 2008 financial crisis was the bankruptcy filing of Wall Street investment bank Lehman Bros. in September of that year, which threw financial markets into chaos.
Under the liquidation authority, regulators would safely shut down a major financial firm in the same way the Federal Deposit Insurance Corp. winds down failing banks.
Republicans have complained the process could be similar to a bailout because it saves financial firms from bankruptcy, therefore encouraging them to engage in speculative behavior. Trump's order directs Mnuchin to determine whether the authority could lead to costs for the Treasury, and hence to taxpayers.
"President Trump is absolutely committed to make sure taxpayers are not at risk for government bailouts of entities that are too big to fail," Mnuchin told reporters.
If regulators' liquidation authority were to be repealed, the move would have to be accompanied by revisions to bankruptcy laws, Mnuchin said.
"The bankruptcy code right now doesn't work, so if entities were going to go through bankruptcy, I think it's important that we have necessary changes to the bankruptcy code," Mnuchin said.
The second memo focuses on the Financial Stability Oversight Council, a panel of top regulators created by Dodd-Frank.
The council has the authority to designate some non-banks as systemically important financial institutions, which face tougher oversight. Banks with more than $50 billion in assets are automatically designated as systemically important.
The memo directs Mnuchin to assess the council's designation process and "the risks created by such designations."
Some lawmakers have wanted the $50-billion level raised so only the biggest banks receive the designation, and have complained that the designation process for non-banks is flawed.
Insurance company MetLife Inc. was designated systemically important in 2014 and sued to have the tag rescinded. A federal judge sided with MetLife last year, but the Obama administration appealed the case.
The bill, called the Financial Choice Act, repeals the orderly-liquidation authority and replaces it with a new bankruptcy process for financial firms with assets of more than $50 billion. The legislation also repeals the Financial Stability Oversight Council's authority to designate firms as systemically important.
Mnuchin said the administration has been working closely with Hensarling but did not say whether it supported the legislation.
12:30 p.m.: This article was updated with President Trump signing the orders and with comments from Trump and additional comments from Treasury Secretary Steven M. Mnuchin.
11:15 a.m.: This article was updated with comments from Sen. Sherrod Brown.
9:30 a.m.: This article was updated with comments from Treasury Secretary Steven Mnuchin.
7:20 a.m.: This article was updated with details about Rep. Jeb Hensarling's Dodd-Frank replacement bill.