Republican presidential candidate Donald Trump. Sarah Rice/Getty Images

Donald Trump, who has championed anti-free-trade and hardline immigration rhetoric on the 2016 presidential campaign trail, had a starkly different tone about globalization in a 2013 op-ed published on CNN's website.

The Republican presidential nominee, writing about how Europe was a "terrific place" for investment, argued at the time that the 2008 recession had made it clear "the global economy has become truly that — global."

Trump wrote that "cultures and economics are intertwined" in today's society, and that it was necessary to "work with each other for the benefit of all."

"My concern is that the negligence of a few will adversely affect the majority," he wrote.

Trump continued: "In this case, the solution is clear. We will have to leave borders behind and go for global unity when it comes to financial stability."

The real-estate mogul concluded his op-ed by writing that the future of the US and Europe "depends on a cohesive global economy."

"All of us must work together toward that very significant common goal," he wrote.

Trump has been a strong critic of trade treaties, opposing the proposed Trans-Pacific Partnership deal and North American Free Trade Agreement, often finding himself at odds with members of his own party by doing so. He has also cheered Great Britain's vote to leave the European Union, claiming parallels exist between his own political rise and the so-called Brexit.

And the billionaire has recently skewered his Democratic rival, Hillary Clinton, for privately expressing a desire for a borderless hemisphere, despite writing in his 2013 op-ed that it would be necessary to "leave borders behind."

A spokesperson for the Trump campaign did not immediately respond to a request for comment.

The op-ed was unearthed just hours before Trump is set to face off with Clinton in the final presidential debate. On Wednesday, Trump trailed the former secretary of state by 6.9 points in a four-way race in the RealClearPolitics national polling average.