Republican Sen. Rand Paul has hit out at the Democratic mayor of Denver for his plans to stop mass deportations of undocumented immigrants under President-elect Donald Trump.

Mayor Mike Johnston has said that he plans to keep immigration officials out of the Colorado city, and warned that his planned resistance could compare to the infamous Tiananmen Square protests in China.

'It's like the Tiananmen Square moment with the rose and the gun, right? You'd have every one of those Highland moms who came out for the migrants. And you do not want to mess with them.'

The mayor was referring to the student-led democracy protests centered on Beijing's Tiananmen Square in 1989, during which tens of thousands of people demanded economic, social and political liberalization after decades of repression under the Chinese Communist Party. 

The protests, though, turned deadly when the Chinese government deployed troops who engaged in bloody clashes with demonstrators, leaving several hundred dead. 

Now, if Johnston were to start a similar protest, Paul said he could be removed from office and could even face potential criminal charges.

'I would say, the mayor of Denver, if he's going to resist federal law - which there's a longstanding, standing history of the supremacy of federal law - [if] he's going to resist that, it will go all the way to the Supreme Court, and I would suspect that he would be removed from office,' the Kentucky senator told Margaret Brennan on Face the Nation Sunday morning.

'I don't know whether or not that would be a criminal prosecution for someone resisting federal law,' he continued. 'But he will lose.

'And people need to realize that what he is offering is a form of insurrection where the states resist the federal government. Most people objected to that and rejected that long ago.

'So I think the mayor of Denver is on the wrong side of history and really, I think, will face legal ramifications if he doesn't obey the federal law.' 

But Paul's criticism of the mayor only came in response to Brennan asking him his thoughts on Trump's proposal to use the military to assist with the mass deportations.

Paul said he is '100 percent supportive of going after the 15,000 murderers, the 13,000 sexual assault predators, rapists, all of these people.

'Let's send them on their way to prison or back home to another prison,' the Kentucky senator replied. 'So I would say, all points bulletin, all in.'

'But you don't do it with the Army because it's illegal,' he continued, noting that police differ from soldiers because they have to follow the Fourth Amendment - which gives Americans a right to unreasonable search and seizure - and have to obtain specific warrants.

'And so, I'm for removing these people,' Paul said. 'But I would do it through the normal process of domestic policing.' 

Deportations had been a cornerstone of Trump's successful campaign.

He had also vowed to halt entries across the US border with Mexico and ending birthright citizenship for children of undocumented immigrants. 

The incoming president is expected to sign a series of executive orders once he takes office in January, including one that would temporarily shut the southern border to give officials a chance to clear a huge backlog of cases.

He will also increase the number of armed officers on horseback patrolling the rugged terrain close to the United States' border with Mexico and resume construction on the border wall, an insider previously told DailyMail.com.

Trump has previously vowed to complete the $8 billion job by inviting businesses to 'sponsor' sections of the wall.

At the same time, the president-elect is expected to begin his mass deportation program by invoking the Alien Enemies Act of 1798, which gives presidents the authority to detain and deport non-citizens from 'hostile nations' during times of war and conflict.

He will use that law as a basis to start targeting undocumented immigrants with ties to international criminal gangs for deportation in a plan dubbed 'Operation Aurora,' after the Colorado town where members of the Venezuelan street gang Tren de Aragua turned apartment complexes into bases for drug dealing and prostitution

According to those familiar with Trump's plans, he will target the 700,000 Venezuelans, Haitians, Cubans and Nicaraguans he has branded 'vicious criminals from countries that hate us', who have been allowed to stay in the US under a Biden parole program. 

Once those deportations are complete, the president-elect plans to expel more than one million people whose applications to remain in the US have been denied and who are on the deportation list, insiders previously DailyMail.com.

Then the round-up of the millions of remaining illegal immigrants will begin as part of 'Step Three'. Places of work, including farms and meatpacking plants, will be subject to raids (or 'targeted enforcement activities') – something the American Civil Liberties Union calls 'vile, unconstitutional and un-American'.

There are currently nearly 12 million undocumented immigrants in the US, according to the Center for Migration Studies. 

Individuals will be taken to 'holding centers' before their deportation is fast-tracked.