President Biden arrived in Belfast, Northern Ireland, for the first time during his presidency Tuesday night to celebrate the 25th anniversary of the Good Friday Agreement and accompanying him were son, Hunter, and sister, Valerie Biden Owens.

Air Force One landed in the capital of Northern Ireland late Tuesday night, and along with his son and sister, Biden was joined by U.S. envoy to Northern Ireland Joseph Patrick Kennedy III, a grandnephew of the late President John F. Kennedy.

U.S. President Joe Biden, Hunter Biden, Valerie Biden Owens

U.S. President Joe Biden, Hunter Biden, and Valerie Biden Owens land in Belfast, Ireland (Fox News)

While in Northern Ireland, the president will embark on a four-day tour to "keep the peace" in the region.

BIDEN TAKES SON HUNTER AND SISTER VALERIE TO IRELAND AS INVESTIGATIONS HEAT UP

Prior to taking off from Andrews Air Force Base in Maryland, Biden declined to provide names of family members who were accompanying him on the trip, though it was clear that his troubled son Hunter, who is currently under investigation, was going along.

"Just two of my family members who haven’t been there before," he told reporters.

U.S. President Joe Biden lands Belfast, Ireland

U.S. President Joe Biden lands in Belfast, Ireland (Fox News)

The president’s decision to bring Hunter to his ancestral country was a staunch signal to Republicans conducting the investigations, though it left some scratching their heads on why he was going on a diplomatic trip.

BIDEN SPOTTED WITH SON HUNTER AT WHITE HOUSE EAST EGG ROLL AS INVESTIGATIONS HEAT UP

The Daily Mail reported that Biden was asked about the trip’s purpose on Tuesday night.

"Make sure the Irish accords and the Windsor agreement stay in place," the president responded. "Keep the peace. That’s the main thing, and it looks like we’re gonna."

The British publication also reported that the Grand Central Hotel was lined with armored vehicles, along with barriers set up to close the street off to traffic.

Joe Biden salutes irish military officer

U.S. President Joe Biden salutes an Irish Military Officer (Fox News)

During Biden’s trip to Northern Ireland, he will reportedly meet with United Kingdom Prime Minister Rishi Sunak, and mark 25 years of peace since the Good Friday Agreement of 1998, which formally ended decades of "The Troubles," a violent conflict between Protestant Unionists loyal to the Crown, and Catholic Republicans supportive of a unified Ireland.

JOE BIDEN MET WITH AT LEAST 14 OF HUNTER BIDEN'S BUSINESS ASSOCIATES WHILE VICE PRESIDENT

Biden is also scheduled to give a speech at Ulster University before leaving for Dublin, where he will meet with Irish President Michael Higgins.

Prior to the president’s trip, security concerns were heightened after gasoline bombs were lobbed at law enforcement by demonstrators in Derry/Londonderry, a hot spot of violence during the Troubles.

Police also foiled a bomb plot planned by the "New IRA" members ahead of Biden’s visit.

Diplomatic intentions aside, Biden also plans to meet with distant relatives during the trip, as the president has frequently stated how important his Irish heritage was in shaping who he is.

HUNTER BIDEN'S BUSINESS PARTNERS, ASSISTANTS VISITED WHITE HOUSE OVER 80 TIMES WHEN BIDEN WAS VP

Biden’s granddaughter, Hunter’s daughter, is named Finnegan, after his mother, Catherine Eugenia Finnegan Biden.

Hunter was seen disembarking from Air Force One in Belfast, as dual federal investigations into the Biden family continue.

The U.S. Attorney’s Office in Delaware kicked off a criminal investigation into the president’s son’s tax and business dealings in 2018, and is ongoing.

Along with the U.S. Attorney’s Office investigation, House Republicans also launched an investigation into Hunter’s business deals and any possible involvement by the president.

President Biden has repeatedly insisted he had no knowledge of his son Hunter's business dealings, despite mounting claims to the contrary.

Fox News Digital previously reported that Biden met with at least 14 of Hunter Biden’s business associates while he was vice president in the Obama White House, and that four business partners, a vice president, and two assistants at Hunter Biden’s now-defunct firm visited the White House more than 80 times when his father was vice president.

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Hunter, who has adamantly denied any wrongdoing, has not been charged with a crime related to the investigations. 

The president has maintained he had no knowledge of his son's business dealings.

Fox News’ Charles Creitz and Paul Best and Jessica Chasmar contributed to this report.