US President-elect Donald Trump has named Pete Hegseth, a Fox News host, author and military veteran, as his pick for defence secretary.

Hegseth, 44, who served in Afghanistan and Iraq, will be responsible for the world’s most powerful military in his first political role.

Announcing his choice on Tuesday, Trump described him as “tough, smart and a true believer in America First”.

The news came on the same day Trump announced another political newcomer, billionaire Elon Musk, would take a government cost-cutting role.

Trump’s administration is taking shape after his win in last week’s presidential election. Hegseth was one of a flurry of security appointments that also included Trump’s pick of John Ratcliffe to head the Central Intelligence Agency (CIA).

If confirmed for his role by the US Senate, Hegseth will arrive at the Pentagon with decisions to make on issues such as military assistance for Israel during its campaign in Gaza, and on support for Ukraine in the face of Russia’s invasion.

Trump wants the US to disentangle itself from foreign conflicts generally. During the election campaign, he criticised the Biden administration’s expenditure to support Kyiv.

Also on Tuesday, Trump confirmed that he wanted South Dakota Governor Kristi Noem to play a significant role as homeland security secretary. Another military veteran, Michael Waltz, was chosen by Trump as national security adviser – meaning he will advise the president on foreign threats.

Senator Marco Rubio – who shares Waltz’s hawkish views on China – is expected to be Trump’s future secretary of state, sources have told the BBC’s US partner, CBS News. But the pick is not yet confirmed.

Republicans have won back control of the Senate, the upper chamber of Congress, and are inching towards a majority in the House, the lower chamber, as vote-counting continues.

Some of the government appointments – including Hegseth’s – require a vote of approval by senators, although Trump, also a Republican, has demanded that the next leader of the US Senate let him bypass this process. He can give out other jobs directly.

Senate Republicans are due to vote on a new leader on Wednesday – the day that Trump is also expected to visit the outgoing president, Joe Biden, at the White House as part of the traditional transfer of power.

Born in Minneapolis, Minnesota, Ivy League graduate Hegseth has in recent years worked as a conservative commentator. He lives with his wife and seven children in Tennessee.

He has hosted programmes on Fox News, using his platform to draw attention to military and veterans’ issues. He had his last day at Fox on Tuesday.

He is reported by US media to have successfully lobbied Trump during his first presidency to pardon servicemen accused of war crimes.

In his statement announcing Hegseth as his pick for defence secretary on Tuesday, Trump highlighted the former soldier’s education at Princeton and Harvard universities, and his military experience in Afghanistan and Iraq.

“With Pete at the helm, America’s enemies are on notice – our military will be great again, and America will never back down,” Trump wrote in a post.

The president-elect also drew attention to Hegseth’s work as a published author. He said the book The War on Warrior “reveals the leftwing betrayal of our warriors, and how we must return our military to meritocracy, lethality, accountability, and excellence”.

Hegseth has been an outspoken opponent of what he has referred to as “woke” policies within the US military and its leadership.

“The dumbest phrase on planet earth in the military is our diversity is our strength,” Hegseth said on a podcast this month.

One of his tasks as defence secretary could be to act on Trump’s campaign promises to get rid of US generals who he accuses of pursuing progressive policies in the force.

Before his selection by Trump, Hegseth was asked on the same podcast about what changes he would make in the military. He referred to “first of all” firing the US’ top military officer, Gen Charles “CQ” Brown Jr, saying people involved in diversity, equality or inclusion policies had “got to go”.

“Either you’re in for war fighting and that’s it, that’s the only litmus test we care about,” Hegseth told the Shawn Ryan Show, in an episode released last week.

Gen Brown is a former fighter pilot with command experience in the Pacific and Middle East, and was appointed into the chairman of the Joint Chiefs of Staff role by President Joe Biden last year.

On the same podcast, Hegseth also said “whatever” combat standards were in 1995, “let’s just make those the standards”.

Hegseth’s pick has been welcomed by a number of prominent Republican figures, but other reactions have been more varied.

North Carolina senator Thom Tillis told Associated Press the choice was “interesting”, and Senator Tommy Tuberville, of Alabama, said he would “have to think” about what he thought of the appointment.

Incoming national security advisor Waltz said Hegseth “has the grit” to make “real reform” happen at the Pentagon. Representative Adam Smith, the top Democrat on the House Armed Services Committee, said the job “should not be an entry-level position”.

Posting on X, Democratic Senator Elizabeth Warren said the appointment of Hegseth as defence secretary would “make us less safe and must be rejected”.

“A Fox & Friends weekend co-host is not qualified to be the Secretary of Defense,” she added. “I lead the Senate military personnel panel. All three of my brothers served in uniform. I respect every one of our servicemembers.”

North America correspondent Anthony Zurcher makes sense of the race for the White House in his twice-weekly US Election Unspun newsletter. Readers in the UK can sign up here. Those outside the UK can sign up here.