Gary Cohn, President Donald Trump's former top economic adviser, spoke out for the first time since leaving the White House.

In an interview with CNBC, Cohn described himself as "anti-tariff" and a "free trader," and he said, "I'm a globalist."

The former Goldman Sachs executive criticized recently announced tariffs and said the moves would be bad for the US economy.

Cohn also weighed in on the GOP tax law and bitcoin.

Gary Cohn, the former top economic adviser to President Donald Trump, reemerged on Tuesday in his first extensive interview since leaving the White House and criticized the president's newest trade policies.

"I think that people are concerned that the economic policies of Washington are not as clear this year as they were last year," Cohn said in an interview with CNBC.

Cohn, the former Goldman Sachs executive, stressed that the recent rash of protectionist trade policies — including announced tariffs on steel, aluminum, and Chinese goods — were foolish.

"In a perfect world, they would be nonexistent," Cohn said of tariffs on Chinese products.

Cohn submitted his resignation on March 6, shortly after Trump announced the tariffs on steel and aluminum. On Tuesday, Cohn reiterated his free-trade stance, calling himself "anti-tariff" and "a free trader" and saying, "I'm a globalist."

"Globalist" was also the word Trump used to describe Cohn during a Cabinet meeting after his resignation. The term has at times been used by far-right groups as an anti-Semitic attack; Cohn is Jewish.

Cohn also argued that the Trump administration's stated goal of imposing tariffs to support the manufacturing industry was misguided. The US economy is primarily focused on services, Cohn said. But by increasing the cost of goods, the administration would ensure that American consumers have less to spend on services, he argued.

"I believe that we are very good at doing certain things in the United States; other countries are very good at doing different things," Cohn said. "We should buy from them what they're good at; we should sell to them what we're good at."

In particular, Cohn took issue with the tariffs' focus on "input products," or parts used to produce finished goods. Economists and trade experts have warned that a focus on "parts" will be problematic for US businesses that rely on imported pieces to create their products.

Cohn cited the aluminum tariffs as an example of the trouble. In various surveys, manufacturers reported that higher aluminum prices over the past two months had caused uncertainty and slowed investment plans.

There are "tens of thousands of more people that are employed in using aluminum than in manufacturing aluminum," Cohn said.

In the interview, Cohn also said that it was too early to judge the effectiveness of the GOP tax law but that early signs were promising.

Cohn also weighed in on bitcoin and cryptocurrency.

"I'm not a big believer in bitcoin — I am a believer in blockchain technology," he said, adding that he thinks there will eventually be a global cryptocurrency.

Watch some of Cohn's comments to CNBC: