Washington (CNN) President Donald Trump again lamented what he views as an unequal military alliance Wednesday, claiming that if the US is attacked, Japan "doesn't have to help us at all" and "can watch it on the Sony television."

Trump's criticism of Japan came during an interview on Fox Business Network when he was asked about the possibility of bilateral trade deals ahead of his G20 trip, where he will meet with several counterparts, including Japanese Prime Minister Shinzo Abe.

"Let me start off with general statement -- almost all countries in this world take tremendous advantage," of the US, Trump told Fox Business by phone, repeating a common refrain of his 2016 campaign.

The President then criticized NATO broadly, before singling out Japan for the terms of its military alliance with the US.

"If Japan is attacked, we will fight World War Three ... with our lives and with our treasure," he said, adding, "If we're attacked, Japan doesn't have to help us at all," Trump said. Japan, he claimed, "can watch it on the Sony television, okay, the attack."

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