Australia has hit back over the Trump administration’s move to raise tariffs on Australian exports to 12.5 per cent, arguing that it is  unjustified.

The US said the latest hike would take effect from 2.01pm on Friday (AEST), replacing a temporary 10 per cent tariff that had been set to expire at the same time.

Dozens of other countries also face steeper tariffs, which were first proposed last month after a US trade investigation into forced labour.

US Trade Representative Jamieson Greer said the trade hit would apply to 60 nations, with the Trump administration claiming it is in response for their failure to stop the importation of goods produced with forced labour.

“President Trump recognises that decades of moral suasion have not eradicated forced labour from global supply chain,” Greer said.

“The United States has had a forced labour import ban for nearly a century, and rigorously enforces it; it’s well past time for our trading partners to do the same.”

But Australian Trade Minister Don Farrell said the latest tariffs on Australia were unjustified, and should not be imposed.

“These tariffs are unjustified, inconsistent with our free trade agreement, and should be removed,” he said on Friday.

“Australia’s measures to combat forced labour and modern slavery are among the strongest in the world, and we are recognised globally, including in the US, for our leadership.”

Deputy Prime Minister Richard Marles said the Australian government was disappointed with the decision.

“We don’t want to see increases in tariffs,” Marles told ABC’s Radio National on Friday. “We want to see freer trade and more trade flows between Australia and the United States.”

The US moves comes just a week after the federal government announced it would strengthen anti-slavery laws, with tougher penalties for Australian companies that haven’t taken reasonable steps to prevent forced labour in their supply chain.

Marles said that while Australia supported the objective of combating force labour globally, it already has laws which are “amongst the strongest in the world”.

“And we’ve been making that point to the Trump administration.”

Australia has already moved to crack down on the use of forced labour in supply chains. Graphic: AAP

An estimated 50 million people across the world are enslaved, according to the Global Slavery Index, with the figure including people who are trafficked and subject to forced labour.

Despite the US framing the increased tariffs as a human rights issue, political observers are viewing this as a workaround to sweeping global tariff imposition that American courts will not consider a presidential overstep.

Friday’s update came a day after US President Donald Trump announced new 50 per cent tariffs on a variety of Canadian products that will take effect on August 19.

In response, Canadian PM Mark Carney said Canada would do whatever it took to defend itself in a trade war with the US, including possible retaliatory measures.

“We are intensifying our trade negotiations with the United States and will not hesitate to defend our interests if ‌we have to,” Carney said, describing the new US measures as unwarranted.

“Everything’s on the table if there’s no agreement.”

–with AAP