Donald Trump expected to enforce unknown 18th-century wartime law to begin mass deportations

The President is storming ahead with his plan to enforce an 18th-century wartime law to fuel mass deportations of immigrants.

Immigration has been a hot topic for the US President, as Donald Trump touted his hard line approach during his campaign trail and signed an executive order to 'protect the American people against invasion' within hours of taking over the White House on January 20.

To this end, he has also slapped Canada, Mexico and China with hefty tariffs to encourage their cooperation in stopping the flow of both migrants and illegal drugs from crossing US borders.

Trump wants to use the law to speed up deportations (Andrew Harnik/Getty Images)

Now, he appears to be pressing ahead with his vision of mass deportations by digging up the Alien Enemies Act of 1798, a relatively unknown 18th century law, and implementing it within the coming days, according to CNN.

The law would allow the Trump administration to fast-track deportations of migrants without any legal barriers.

For instance, the act could be used to deport non-US citizens who have been accused of being gang members without any court hearings taking place, and as such, it is likely to face fierce legal opposition.

The 1798 Enemies Act was commissioned in response to spying and sabotage during tensions with France at the time, as per The Independent, and was passed shortly after the US was liberated from the British Empire.

Deportations are already underway in the US but Trump is hoping to speed the process up (Emilio Flores/Anadolu via Getty Images)

According to the act, it can be revoked during a 'declared war' or 'any invasion or predatory incursion' against the US government from a foreign government, and contains four laws that restrict the rights of foreign-born Americans, according to the National Archives.

Until the President terminates it, it can remain in action for however long as necessary.

It reads: "Whenever there shall be a declared war between the United States and any foreign nation or government … and the President of the United States shall make public proclamation of the event, all natives, citizens, denizens, or subjects of the hostile nation or government, being males of the age of fourteen years and upwards, who shall be within the United States, and not actually naturalized, shall be liable to be apprehended, restrained, secured and removed, as alien enemies.”

It has already been used three times in the US throughout history - the last being to justify internment camps for Japanese, German and Italian citizens, who were the Axis powers at the time, during the Second World War.

The US President has signed an executive order to crackdown on immigration in the US (Win McNamee/Getty Images)

President Franklin Roosevelt signed off on the act, having deemed them 'alien enemies.'

In 1812, it was also used against the British, who were required to report information such as place of residence, length of time in the US, and whether they'd applied for naturalisation, as per NPR.

Then in World War I, the law was used by President Woodrow Wilson against nationals from the German Empire, Austria, Hungary, the Ottoman Empire and Bulgaria, as the NPR states 6,000 'enemy aliens' - largely Germans - remained in internment camps for two years following the war's conclusion in 1918.

Trump has repeatedly told his supporters that he will utilize the law to rid the US of all illegal immigrants, with sources allegedly telling CNN that the primary target is a Venezuelan organized crime group, Tren de Aragua (TDA), that is operating in the US and other countries.

Trump previously said: "I will invoke the Alien Enemies Act of 1798 to target and dismantle every migrant criminal network operating on American soil."