WASHINGTON (NewsNation Now) — President Joe Biden laid out a new goal for COVID-19 vaccinations at his first formal news conference Thursday, pledging to have 200 million doses administered by the end of his first 100 days in office. That’s double the goal he set in December and reached earlier this month before his 60th day in office.

“I know it’s ambitious, twice our original goal, but no other country in the world has even come close,” said Biden.

Biden said he also expects to run for president again in 2024 and defended his policy to provide shelter to unaccompanied children crossing the U.S. border from Mexico at his first solo news conference since taking office.

“My answer is yes, my plan is to run for reelection,” he said. “That’s my expectation.”

Biden also added he planned to keep Vice President Kamala Harris as his running mate.

Biden was repeatedly pressed to defend his migration policy along the border with Mexico. He said the increase in migration was cyclical.

“It happens every single solitary year. There is a significant increase in the number of people coming to the border in the winter months,” he said. “It happens every year.”

He said many migrants were fleeing problems in their home countries and blamed former President Donald Trump, for dismantling parts of the U.S. immigration system.

Biden also called for Republicans in Congress to help him move forward with his agenda or “continue the politics of division” as he takes on issues like gun control, climate change and immigration reform.

“I’ve been hired to solve problems, not create division,” Biden said.

Biden also said a May 1 deadline to withdraw troops in Afghanistan will be difficult to meet. “It’s going to be hard to meet the May 1 deadline,” he said. But he added, “We are not staying a long time” in Afghanistan, site of America’s longest war.

Just a few dozen journalists from news outlets selected by the White House Correspondents’ Association are on hand in the East Room Thursday, due to restrictions related to the pandemic.

Though Biden has talked to the media in other settings since taking office, he’s the first chief executive in four decades to reach this point in his term without holding a formal question-and-answer session. 

“It’s an opportunity for him to speak to the American people, obviously directly through the coverage, directly through all of you,” White House press secretary Jen Psaki told reporters aboard Air Force One on Tuesday. “And so I think he’s thinking about what he wants to say, what he wants to convey, where he can provide updates, and, you know, looking forward to the opportunity to engage with a free press.”

The president’s first official press conference comes in the wake of a series of shootings in Colorado and Georgia killed 18 people in less than a week.

Biden said Thursday that successful gun control measures are a matter of timing. On Tuesday, Biden called for a ban on assault weapons and urged lawmakers to close loopholes in the background check system. Republican support for gun control measures remains low.

The president’s appearance also came just a day after he appointed Harris to lead the government’s response to the situation at the U.S.-Mexico border, where the administration faces a growing humanitarian and political challenge that threatens to overshadow Biden’s legislative agenda.

Biden is poised for his next big congressional ask. He’s expected to unveil a roughly $3 trillion bill to boost U.S. infrastructure during a trip to Pittsburgh next week.

The Associated Press and Reuters contributed to this report. Reporting by AP’s Jonathan Lemire and Zeke Miller, and Reuters’ Jeff Mason.