The US President has announced a 20% tariff on imports from the European Union while foreign-made vehicles face a 25% levy from tomorrow.
Donald Trump said the 20% figure is about half of the EU levy on US goods.
He also confirmed a 10% tariff on the UK.
Alongside the reciprocal tariffs, Donald Trump also said that he would impose a 10% baseline tariff on all imports to the US.
President Trump said the implementation of "reciprocal" - or retaliatory - tariffs on countries worldwide is a "declaration of economic independence".
"Reciprocal that means: they do it to us, and we do it to them," he said at the White House.
"The numbers are so disproportionate, they're so unfair. We're going to have a minimum of cheating.
"Countries will finally be asked to pay for the privilege of access to our market, the biggest market in the world.
"This is one of the most important days, in my opinion, in American history."
A White House official, speaking on condition of anonymity, said the higher penalties will take effect on 9 April and will apply to about 60 countries in all.
The baseline 10% tariff will take effect on Saturday, the official said.
Mr Trump said the move will mean "lower prices for consumers" in his country and that "jobs and factories will come back".
The sweeping tariffs come on what he proclaimed as "Liberation Day" for the United States, escalating a trade war with global partners, risking cost increases and upending a decades-old trade order.
A separate 25% global tariff on automotive imports will take effect tomorrow.
They are also expected to spark retaliatory action from global trading partners.
Significant concerns have been raised for specific sectors in Ireland, including the pharmaceutical and spirits industries.
A fact sheet released by the White House said that pharmaceuticals are not currently subject to the reciprocal tariff, but adds that future good-specific or sector-specific tariffs may be announced.
While pharmaceutical products are not subject to the 20% tariff it is not yet clear if they are exempt from the 10% baseline tariff.
'Our country has been looted, pillaged, raped and plundered' - Trump
US stock futures dropped sharply after the announcement, following weeks of volatile trading as investors speculated about how the incoming tariffs might affect the global economy, inflation and corporate earnings.
US stocks have erased nearly $5 trillion of value since February.
Chinese imports will be hit with a 34% tariff, on top of the 20% he previously imposed, bringing the total new levy to 54%.
Canada and Mexico, the two largest US trading partners, already face 25% tariffs on many goods and will not face additional levies from the announcement.
"For decades, our country has been looted, pillaged, raped and plundered by nations near and far, both friend and foe alike," Mr Trump said at an event in the White House Rose Garden.
"For decades, the United States slashed our trade barriers on other countries while those nations placed massive tariffs on our products and created outrageous non-monetary barriers to decimate our industries.
"In many cases, the non-monetary barriers were worse than the monetary ones.
"They manipulated their currency, subsidised their exports, stole our intellectual property, imposed exorbitant VAT taxes to disadvantage our products, adopted unfair rules and technical standards and created filthy pollution havens.
"They were absolutely filthy, but they always came to us and they said we're violating we should pay for it."
Confirming the imposition of tariffs of 25% on all foreign-made vehicles, Mr Trump said: "I don't blame these other countries at all.
"I blame former presidents and past leaders. They let it happen to an extent that nobody can even believe."
Last night, Mr Trump met his trade team to discuss the measures.
The president, who once called the word tariff the "most beautiful word in the dictionary", said that his reciprocal plans are a move to equalise generally lower US rates with those charged by other countries and counteract their non-tariff barriers that he says disadvantage US exports.
His levies will be negative for all, European Central Bank President Christine Lagarde said.
"It will be negative the world over and the density and the durability of the impact will vary depending on the scope, on the products targeted, on how long it lasts, on whether or not there are negotiations," she said in an interview on Newstalk.
The tariffs could have huge ramifications across the European Union - particularly for the pharmaceutical industry in Ireland.
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After today, the Government faces important negotiations with the EU about potential reciprocal levels.
Mnisters will want to ensure that any actions by Brussels will not compound the damage caused by Mr Trump's announcement.
It is expected to be difficult for the 27 EU member states to reach an agreed position on how the trading bloc reacts.
The move also underscores the growing and profound gulf between the US and many of its closest allies, not only on trade but on other issues such as security and defence.
Read more:
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