Economic guru Nouriel Roubini warns investors that Wall Street might be underestimating the negatives lurking beneath President Trump's agenda despite stocks seemingly hitting record highs every day.

"Now, the biggest elephant in the room is the United States," Roubini told CNNMoney.

Roubini said that the "biggest uncertainty in the world and biggest tail risk comes from the economic, foreign and security policies of the Trump administration."

The New York University professor explained that because the U.S. is the world's biggest economy, the consequences of a "severe policy mistake" can be enormous, CNN explained.

"Markets are overestimating the positives and underestimating the negatives" from Trump's policies, Roubini told CNNMoney.

Roubini, who slammed the Trump administration as "incompetent," pointed to several specific risks: protectionist policy sparks a trade war; closing borders makes it hard to attract skilled talent from overseas; dramatic tax cuts blow up the US deficit.

"We don't need more tax cuts for the rich and the corporate. That's actually going to make the economy worse," Roubini said.

For his part, veteran financial guru and former Ronald Reagan adviser Larry Kudlow is urging any impatient investors to just give Trump a chance to fully enact his strategies to reform healthcare, spark economic growth and redesign the tax system.

After all, Trump has been in office a relatively short time and has inherited a mountain of problems from the past two decades. “He's trying to fix a lot of problems that have gone unfixed in the last 20 years,” Kudlow explained to CNBC.

Meanwhile, many other respected economic voices are predicting robust growth and additional stock-market gains amid Trump's blueprint to truly "Make America Great Again."

David Horowitz, author of the best-selling book "Big Agenda: President Trump's Plan to Save America," told Newsmax TV that the market rally since Republican Donald Trump won the election has more room for gains as the president pushes his pro-business agenda.

“There's more upside. Starting from when he was president-elect he started this stock market boom,” he told Newsmax TV's “The Income Generation Show.”

“There will be corrections. There are going to be setbacks along the way like the healthcare which they hurried too fast. If you're looking over the long term of this administration I think the stock market is going to love Trump,” Horowitz said.

(Newsmax wires services contributed to this report).

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