Beijing: China has lodged a diplomatic protest after US President-elect Donald Trump broke with decades of diplomatic protocol by holding direct talks with Taiwanese President Tsai Ing-wen.

But Beijing also sought to play down the significance of the 10-minute telephone call held between Mr Trump and Ms Tsai on Friday, with Foreign Minister Wang Yi blaming the exchange on Taiwan's "petty action" while noting the White House's immediate affirmation of the so-called one-China policy.

"The one-China policy is the bedrock of the healthy development of Sino-American relations," Mr Wang told reporters at an academic forum in Beijing on Saturday. "We do not wish to see this political foundation meet with any disruption or damage."

China's foreign ministry said Saturday it had lodged "stern representations" with what it described as the "relevant US side", without elaborating specifically whether this included the Trump transition team directly. It urged the careful handling of the Taiwan issue to avoid any unnecessary disturbances in ties.