BEIJING—In its first briefing since a phone call between U.S. President-elect Donald Trump and Taiwan President Tsai Ing-wen, China's Foreign Ministry said Mr. Trump's people understand the importance of the issue to Beijing.

"Taiwan-related issues are the most important and sensitive part of the China-U.S relationship," ministry spokesman Lu Kang told a packed briefing room on Monday. "We believe Trump's transition team is very clear on that."

Mr. Lu faced a fusillade of questions from foreign reporters about the call, which broke with nearly four decades of U.S. protocol and sparked concerns about blowback from Beijing, which considers Taiwan part of Chinese territory.

He didn't elaborate on any communication China has had with Mr. Trump's camp, but suggested that Beijing had made its displeasure directly known to members of the president-elect's team.

"We have launched representations with the relevant party in the U.S.," he said.

Asked to identify the "relevant party," Mr. Lu demurred: "I think it's easy to understand who the relevant party is."

Mr. Lu declined to be drawn on a series of Sunday evening tweets in which the president-elect blasted China over its currency policy and actions in the South China Sea.

"We have no comment on what motivated the Trump team to make such tweets," Mr. Lu said.

"I know the media in the U.S. made a lot of comments on President-elect Trump during his campaign season and after his election—but for us, for China, we do not comment on his personality. We focus on his policies," said Mr. Lu, who fielded nearly 20 questions on Mr. Trump over the course of the half-hour briefing.

Chinese officials and state media have been restrained in their response to Mr. Trump's talk with Ms. Tsai. Beijing lodged a formal complaint with the U.S., while the country's State Council Taiwan Affairs Office declared the phone exchange "can't change Taiwan's status as a part of China."

State-run nationalist tabloid the Global Times called the phone conversation "jaw-dropping" and declared in an editorial that Mr. Trump "has zero diplomatic experience and is unaware of the repercussions of shaking up Sino-U.S. relations."

Still, the editorial said, it would be inappropriate to target Mr. Trump, as he's not yet in office, and added that it would be best to engage in "constructive" conversations.

Write to Te-Ping Chen at te-ping.chen@wsj.com

(END) Dow Jones Newswires

December 05, 2016 05:45 ET (10:45 GMT)

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