By David Brunnstrom, Simon Lewis and Alasdair Pal WASHINGTON (Reuters) - The United States, Australia, India and Japan recommitted to working together on Tuesday, after the first meeting of the China-focused "Quad" grouping's top diplomats since President Donald Trump returned to the White House.

U.S. lawmakers introduced a bipartisan bill on Thursday that would revoke China's preferential trade status with the United States, phase in steep tariffs and end the "de minimis" exemption for low-value Chinese imports.

China's relations are starting to improve with Japan, India and other countries that former U.S. President Joe Biden courted, just as Donald Trump brings his more unilateralist approach back to the White House.

Rubio's appointment as secretary of state has been seen as sign that Trump plans to maintain a hard line on China.

US Secretary of State Marco Rubio on his first full day in office Tuesday warned jointly with Japan, India and Australia against coercive actions in Asia, in a veiled but clear warning to China over its actions at sea.

Fortunately, Singapore Prime Minister Lawrence Wong thought a full split was unlikely: "I can’t see how a full decoupling can happen at this stage."

Whether it is over TikTok, fentanyl or trade, Beijing might welcome a compromise to buy time to address its ailing economy and bolster its position globally.

Two Iranian cargo vessels carrying an ingredient for missile propellant will sail from China to Iran in the next few weeks, the Financial Times reported on Wednesday, citing intelligence from security officials in two Western countries.

Potential TikTok buyers are lining up as President Trump and the Chinese government show heightened interest in striking a deal to sell the popular video-sharing platform in the face of a U.S.

In China, Apple’s second largest market, iPhone sales fell 18% in the December ending quarter, according to Bloomberg.

BANGKOK — World shares were mixed on Thursday after China rolled out more moves to try to boost its lagging stock markets by raising confidence that prices will rise. Germany’s DAX gained 0.2% to 21,300 and the CAC 40 in Paris edged 0.1% higher to 7,847.38. Britain’s FTSE 100 slipped less than 0.1% to 8,539.88.