WASHINGTON — Karine Jean-Pierre will be the next White House press secretary, President Biden announced on Thursday. She will be the first black woman and openly LGBTQ person to serve in the role, with incumbent Jennifer Psaki set to leave the post next week.

Ms. Jean-Pierre takes on the role as the White House faces an uphill battle to help Democrats hold onto the House and Senate in this fall’s midterm elections, and as the administration struggles to address Americans’ concerns about soaring inflation and the state of the economy.

She also comes into the job as Mr. Biden faces a daunting array of foreign policy challenges, including the ongoing Russian invasion of Ukraine and North Korea’s escalating nuclear testing program. Mr. Biden is set to visit South Korea and Japan later this month and Europe in June.

Mr. Biden is also bringing back a longtime Democratic strategist, Anita Dunn, as his senior adviser. She had served in the Biden White House last year for several months after Mr. Biden was sworn into office.

“Karine not only brings the experience, talent and integrity needed for this difficult job, but she will continue to lead the way in communicating about the work of the Biden-Harris administration on behalf of the American people,” Mr. Biden said in a statement praising Ms. Jean-Pierre, who has served as his principal deputy press secretary since Inauguration Day.

Ms. Psaki, who leaves the White House on May 13, praised her successor, noting the significance of the history-making appointment.

“Representation matters and she will give a voice to many, but also make many dream big about what is truly possible,” Ms. Psaki said.

She said Mr. Biden offered the job to Ms. Jean-Pierre Thursday in the Oval Office. White House staffers were gathered after the offer and greeted Ms. Jean-Pierre with applause, an official said. Two “warm bottles” of champagne was procured for a toast in paper White House cups, the official added, speaking on the condition of anonymity to describe the internal gathering.

When Ms. Jean-Pierre delivered her first press briefing last year, she told reporters, “it’s a real honor to just be standing here today.”

“I appreciate the historic nature, I really do,” she said.

She had occasionally took the lectern in the press briefing room instead of Ms. Psaki and more frequently held off-camera “gaggles” with reporters when Mr. Biden was traveling on Air Force One. She traveled with Mr. Biden to Europe last fall in March instead of Ms. Psaki, who had tested positive for COVID-19 before both trips.

Before joining the Biden presidential campaign, Ms. Jean-Pierre was the chief public affairs officer of the progressive group MoveOn.org and a former political analyst for NBC and MSNBC. She also worked in political affairs in the Obama White House and on his re-election campaign.

The press secretary is responsible for holding daily briefings with the news media and leading a department of more than a dozen staffers who help address queries from the press.

When she took the job, Ms. Psaki, who has two young children, said publicly she aimed to remain in the job for about a year. She is expected to be joining MSNBC later this year.

Mr. Biden said Ms. Psaki “has set the standard for returning decency, respect and decorum to the White House briefing room.”

“I want to say thank you to Jen for raising the bar, communicating directly and truthfully to the American people, and keeping her sense of humor while doing so,” Mr. Biden said. “I thank Jen for her service to the country, and wish her the very best as she moves forward.”

Ms. Dunn is a partner at the Democratic consulting firm SKDK, and was a senior adviser on Mr. Biden’s 2020 campaign and previously chief strategist and communications director for President Obama. The White House said she is returning to “assist in advancing the President’s policy and communications objectives.”