The national emergency Trump used to justify his sweeping tariffs is a “figment of his own imagination,” argued a group of small businesses that urged a federal court to declare the tariffs unlawful.

In a lawsuit filed Monday in the Court of International Trade in New York, the group of businesses alleged that the law used to invoke the tariffs -- the International Emergency Economic Powers Act -- does not empower Trump to unilaterally impose tariffs.

“The President of the United States claims the authority to unilaterally levy tariffs on goods imported from any and every country in the world, at any rate, calculated via any methodology—or mere caprice—immediately, with no notice, or public comment, or phase-in, or delay in implementation, despite massive economic impacts that are likely to do severe damage to the global economy,” the lawsuit said.

While Trump cited the country’s trade deficits to justify the tariffs, the lawsuit argued that the longstanding trade deficits between the U.S. and its trading partners is not an “unusual and extraordinary threat” needed to declare an emergency.

“This Court should declare the President’s unprecedented power grab illegal, enjoin the operation of the executive actions that purport to impose these tariffs under the IEEPA, and reaffirm this country’s core founding principle: there shall be no taxation without representation,” the lawsuit said.

The lawsuit was filed in a New York-based federal court that adjudicates trade laws and brought by five small businesses, including a New York liquor distributor, a Utah-based plastic pipe company, a Virginia-based educational equipment company, a Pennsylvania fishing and tackle outfitter, and a Vermont-based brand of cycling apparel.

The lawsuit marks the second case to challenge Trump’s tariff and the first to specifically call into question the sweeping measures imposed on what Trump called “Liberation Day” earlier this month.

-ABC News’ Peter Charalambous and Katherine Faulders

The White House is taking steps to move towards implementing new tariffs on semiconductors and pharmaceuticals, as Trump said earlier.

Copies of federal notices put online Monday show that the Department of Commerce initiated a public comment period for two Section 232 investigations of pharmaceutical and semiconductor-related products, including the machines used to make chips, and ingredients used for pharmaceutical production.

According to the notices, the investigation began on April 1.

The investigation itself does not implement tariffs, but could signal President Trump will move forward with new tariffs.

Trump has used Section 232 of the Trade Expansion Act of 1962 previously to implement tariffs on steel and aluminum imports as well.

-ABC News’ Molly Nagle

Treasury Secretary Scott Bessent said the U.S. is “moving quickly with many of our most important trading partners” and has meetings in coming days with Japan and South Korea.

“So, we had Vietnam in last week. We have Japanese in on Wednesday, South Korea next week. So, it's going to move fast, and we but the important thing for your viewers to know is we're setting up a process, and we are going to run the process,” Bessent said in an interview with Bloomberg TV in Argentina.

It's going to be orderly, and at the end of the day, especially for the most important trade partners, the president is going,” Bessent said.

Pressed on how many countries he expected the U.S. to strike a deal with before the 90-day pause is up, Bessent painted an optimistic, but vague picture.

“ I think there could be numerous countries, and it may not be the actual trade document, but we will have agreement in principle and be able to move forward from there,” Bessent said.

Pressed again for a general sense of how many countries they expected to get a deal with, Bessent again was vague.

“I think it's going to depend, but we're going to move with all deliberate speed. And again, it's going to be a process. It's going to be USTR, who just has mountains of data that they've been collecting over the years. Because, in a funny way, the tariffs are the easiest part. So a country with high tariffs, you can just say, ‘OK, this, this, this, this, get rid of it. It's the non-tariff trade barriers that are more insidious, more difficult to spot, and it's probably going to take a little longer,” he said.

Asked if he would be able to provide clarity once the 90 days are up, Bessent replied, “I think clarity is through the eye of the beholder, but I can guarantee you that we're going to run a robust process, and I think the market can take great comfort in that,” Bessent said.

-ABC News’ Molly Nagle and Hannah Demissie

President Donald Trump said Monday he's considering tariff exemptions on imported components for U.S. auto manufacturers as they switch to parts manufactured in the U.S.

"I'm looking at something to help some of the car companies where they're switching to parts that were made in Canada, Mexico and other places," Trump said. "And they need a little bit of time. Because they're going to make them here. But they need a little bit of time. So I'm talking about things like that."

Tariffs of 25% on vehicles imported into the United States went into effect earlier this month. Tariffs of 25% on imported auto parts, including engines and electrical components, are set to go into effect later.