Marco Rubio has been confirmed by the Senate for secretary of state with unanimous support. Now comes the hard part that could make or break his tenure: retaining the full backing of his new boss, Donald Trump.

The US' new top diplomat Marco Rubio reaffirmed the country's "unwavering support" for Israel, days into a fragile ceasefire in the Gaza Strip and a large-scale raid in the illegally occupied West Bank.

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

The Senate has unanimously confirmed Marco Rubio as secretary of State; he will be the first Latino to serve as the nation's top diplomat.

On his first full day as secretary of state, Marco Rubio is meeting with his counterparts from a group of countries known as the Quad: the United States plus India, Japan and Australia, representing nearly 2 billion people and more than a third of global GDP.

He was also a candidate in the 2016 GOP presidential primary race, where Trump dubbed him "Little Marco" and Rubio warned voters not to support Trump, saying "friends do not let friends vote for ...

Washington — Sen. Marco Rubio, President-elect Donald Trump's pick to lead the State Department as secretary of state, called China "the most potent and dangerous near-peer adversary this nation ...

Like the Trump presidency, Rubio placed mass migration and border security at the top of his priorities list. Marco Rubio, Donald Trump’s newly-confirmed secretary of state, has assumed office with gusto,

Jeanne Mancini, outgoing president of March for Life, told the the Washington Examiner that she is “just delighted” that former Sen. Marco Rubio was confirmed as secretary of state, even though it meant Congress lost a top anti-abortion legislator,

Tensions between the U.S. and China have been rising for some time now, and Rubio's appointment has widely been seen as a sign that Trump plans to maintain a hard line on China during his second term. One of the most outspoken China hawks in Washington, Rubio has introduced several bills targeting the Chinese Communist Party.

Rubio will depart on his first foreign trip to visit countries in Central America that may be vital for carrying out the Trump administration's mass deportation plans.