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.

On his first full day as U.S. secretary of State, Marco Rubio is meeting with his counterparts from Australia, India and Japan. The four countries are known as the Quad.

Rubio called China the "most potent, dangerous adversary" during his confirmation and is expected to work with India, Japan, and Australia to counter this.

A record number of US companies in China are thinking about moving some operations out of the country or are already in the process of doing so, according to a new study, as geopolitical tensions rise with Donald Trump’s return to the White House.

This week, the mercurial magnate said 10 percent tariffs on all Chinese imports could kick in on February 1 -- and on the campaign trail touted a levy as high as 60 percent.