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.

Analysts say Trump’s threat to impose tariffs on Chinese imports may be a way to extract concessions from Beijing