President Trump plans to nominate L. Brent Bozell III, a conservative media critic and fierce defender of Israel, to be the U.S. ambassador to South Africa, according to the Congressional website.

Mr. Bozell had previously been nominated to lead the United States’ global media agency, but that nomination was withdrawn on Monday, the Congressional website had said.

Mr. Bozell’s name was one of several submitted to the Senate on Tuesday for various ambassador posts, according to two government officials, who requested anonymity because they were not authorized to speak publicly about the process. The State Department declined to comment.

Mr. Bozell, who must be confirmed by the Senate, would be stepping into the role at a time when the relationship between South Africa and the United States is at its worst in recent memory. The Trump administration recently expelled South Africa’s ambassador to the United States after he criticized Mr. Trump during a webinar.

The Trump administration has criticized the South African government over its close relationship with Iran and for its harsh stance against Israel, including bringing a genocide case at the International Court of Justice over the war in Gaza.

It was not immediately clear whether Mr. Bozell had ties to South Africa. He is the founder and president of the Media Research Center, a watchdog group that targets network television hosts and mainstream media outlets with accusations of liberal bias. Once a critic of Mr. Trump, Mr. Bozell is now firmly in his corner. His son, Leo Brent Bozell IV, was one of the nearly 1,600 people convicted and sentenced in the Jan. 6, 2021, attack on the Capitol, but was pardoned by Mr. Trump.

Mr. Bozell has been a vocal supporter of the Israeli government. After Hamas attacked Israel in October 2023, Mr. Bozell posted a fund-raising appeal for Israel on his center’s website, saying that he did not usually make appeals for outside causes but was making an exception because “this is an emergency.”

“Israel is fighting for its very existence,” he wrote.

The Trump administration has also accused South Africa’s government of discriminating against the white minority population. Mr. Trump issued an executive order last month that suspended all American aid to South Africa and offered refugee status to Afrikaners, a white ethnic minority that once led the apartheid government.

Elon Musk, who was born in South Africa, has frequently posted messages on X disparaging the South African government, falsely claiming that there have been mass killings of white farmers. He has also claimed that his satellite business, Starlink, was not allowed to operate in South Africa because he is not Black. (The country requires foreign companies to give ownership shares to members of historically disadvantaged groups.)

South African officials have been taken aback by the attacks from Mr. Trump, Mr. Musk and Secretary of State Marco Rubio, saying that they are based on misinformation.