The US Senate has narrowly confirmed Pete Hegseth as the defense secretary despite lingering questions about his qualifications even among some Republicans.

Senators voted on Friday on whether to confirm Hegseth, who was nominated by President Donald Trump.

Reports say Hegseth was the subject of a police investigation into an alleged sexual assault. He is also on record as saying female soldiers should not be on the battlefield.

Some Republicans joined Democrats to vote against him, bringing the vote count to a 50-50 tie. Vice President JD Vance cast the tie-breaking vote.

US media say this was the second time in US history that a vice president was called upon to break a tie on a Cabinet nominee. The first was in 2017 at the start of the first Trump administration.

Hegseth has stressed that the US military should focus on China. He told a Senate committee hearing on January 14, " We will work with our partners and allies to deter aggression in the Indo-Pacific from the communist Chinese."

Meanwhile, the New York Times reports that a portrait has been removed from a Pentagon hallway. The painting was a depiction of a former chairman of the Joint Chiefs of Staff who was known to be critical of Trump. The newspaper's headline read, "Trump Pulls the Military Back Into the Political and Culture Wars."