China issued an upbeat but vague promise today to carry out a tariff ceasefire with Washington but gave no details that might dispel confusion about what Presidents Xi Jinping and Donald Trump agreed to in Argentina.

China has yet to confirm Trump's claim that Beijing committed to cut auto tariffs and buy more American farm exports. That, coupled with conflicting statements by Trump and US officials, helped trigger a tumble in US stock prices on Tuesday amid doubt about the chances for a lasting settlement of a battle over technology that threatens to chill global economic growth.

"China will start from implementing specific issues on which consensus has been reached, and the sooner, the better," the Commerce Ministry said on its website.

The two sides have a "clear timetable and road map" for talks, the ministry said, but gave no details. The ministry didn't respond to questions by phone and fax.

The Chinese silence prompted questions about what Trump said was a promise by Beijing to buy more American exports and negotiate over US complaints that it steals American technology.

Read more: Trump Flirts with “Read My Lips” Moment with China Deal

Stock markets rose on Monday after US officials touted the agreement as a historic breakthrough. But they plunged on Tuesday after Trump called himself "Tariff Man" on Twitter and renewed threats of penalty duties.

Be patient, said Ma Hong, a trade expert at Tsinghua University in Beijing. He said Chinese leaders are right to move carefully as they deal with contentious details.

The delay in talking "isn't a sign of rejection, but of cautiousness," said Ma.

"The United States has put forward many demands, not all of them reasonable," he said. Negotiations will proceed "step by step, not based on the rhythm of the United States."

Trump is pressing Beijing to roll back plans for state-led development of Chinese technology champions that Washington says violate its market-opening commitments.

Chinese leaders have offered to change some details of plans such as "Made in China 2025". They have rejected pressure to scrap strategies they see as a path to prosperity and global influence, but foreign analysts say they might be starting to understand the depth of foreign opposition to their plans.

Beijing has tried without success to recruit Europe, South Korea and other countries as allies against Trump. They criticise Washington's tactics but share its complaints.

This week's confusion highlights the clash between the secrecy and measured pace of the ruling Communist Party and Trump, who fires off dozens of Twitter comments a day and cultivates an image as a fast-paced, unpredictable deal-maker.

Chinese leaders routinely use delays of months or years to pressure negotiating partners.

Even on routine matters, with no voters to placate and total control of Chinese media, they can frustrate other governments by leaving them waiting weeks or months for a response.