If the agency finds the regulation harms investors or firms, Mr. Trump said it should modify or repeal the rule, which requires all financial advisers to act in the best interests of their clients in retirement accounts.
But critics in the business world say the rule is overly broad and will have disastrous consequences, cutting off investment advice to people with lower incomes.
There will also be a 45-day comment period on President Donald Trump's executive memo, which directs the Labor Department to examine the rule and analyze its economic impacts.
The U.S. Chamber of Commerce appealed a Texas federal judge's ruling upholding a Labor Department's regulation aimed at putting retirement savers' interest first on Friday, the latest salvo in the securities industry's fight against the regulation.
With regard to President Trump's February 3 Executive Memorandum that directed the Labor Department to essentially reconsider the impact of the fiduciary regulation on investors, retirees, the industry, advice access, pricing and litigation, the Labor Department will be seeking comments for the next 45 days, according to a proposed rule released March 1.
In anticipation of the rule, some financial firms have lowered fees, introduced simpler fee structures or eliminated commission-based retirement accounts.
The so-called "fiduciary rule" was set to go into effect on April 10 and would have prohibited retirement advisers from accepting incentives for promoting certain funds over others.
The Labor Department is now running without a leader.
The fiduciary rule was created under the Obama administration past year. A 15-day comment period will commence tomorrow.
Micah Hauptman, financial services counsel at the Consumer Federation of America, pointed to language in the delay proposal that said it would be effective on the date of the publication of the final rule in the Federal Register, which is likely to occur in late March or early April after the DOL has reviewed comments on the delay and the Office of Management and Budget has approved it.
On Wednesday, the Securities Industry and Financial Markets Assn, which represents securities firms, banks and asset managers, said the pending rule already had caused some firms to announce they no longer would offer some products and make other changes that harm Americans' access to retirement offerings.
The Financial Services Roundtable, a lobbying group, issued a statement praising the delay.