On Saturday, China's Defense Ministry released a statement announcing that its military had come across an unmanned American device in the South China Sea on Dec. 15 and said it would transfer the drone to the U.S. The move prompted an angry response from Trump, who tweeted over the weekend that Washington should refuse to accept the drone , reflecting an increasingly tougher stance against the world's second-largest economy.

China's recent seizure of a U.S Navy underwater drone may have been an early political test for U.S. president-elect Donald Trump .

A satellite image of Subi Reef, an artificial island being developed by China in the Spratly Islands in the South China Sea, on September 4, 2016.

The drone episode was merely a means to assess Trump's view on the issue of U.S. maritime surveillance, Aaron Connelly, research fellow at Lowy Institute for International Policy, told CNBC's "Squawk Box Asia" on Wednesday.

As Beijing aggressively constructs artificial islands in the 3.2 million square kilometer South China Sea to house future logistical bases, Washington has maintained active reconnaissance missions in the area to keep an eye on China's military presence, thus creating a hotbed of tensions.

"The Chinese have regularly tested new U.S. administrations when it comes to surveillance; it happened in 2001 and 2009," Connelly explained. "The data gleaned from this surveillance makes it easier for the U.S. navy to detect Chinese submarines and that's been one of Beijing's regular gripes about U.S. sea power in the area."

Many observers have noted the timing of the drone incident, flagging that it may be retaliation for Trump's recent phone call with Taiwanese President Tsai or his controversial comments about the One-China policy.

Connelly doesn't buy that view, however.

"That would have been a very oblique way to make that point as nothing about the drone had anything to do with Taiwan, so I suspect its primarily about surveillance activities."

What's significant about the entire affair is how far the U.S. drone was from Chinese territory, he said.

"Previous harassment of U.S. navy ships occurred much closer to the Chinese mainland but this incident took place as about 600 kilometers away, and it was even outside the Chinese nine-dash line, which Beijing has used to claim much of the South China Sea," Connelly explained.

The entire episode reflects just how serious China is about the expansion of its maritime rights, he continued.

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