President Trump and former President Biden attend Pope Francis' funeral. See photos.

World leaders including President Donald Trumpand former President Joe Biden convened in Rome for the funeral of Pope Francis.

Other world leaders in attendance included include UK Prime Minister Keir Starmer and Britain's Prince William, U.N. Secretary General Antonio Guterres, French President Emmanuel Macron and Ukrainian President Volodymyr Zelenskyy.

In all, more than a quarter-million people gathered in St. Peter’s Square for Pope Francis’ funeral on Saturday, April 26. After the two-hour service, Francis was laid to rest in a private, religious afternoon ceremony within the Basilica of Saint Mary Major.

Trump and Pope Francis had clashed over the president's plans to deport millions of migrants from the U.S., with the pope calling Trump's plan a "major crisis" for the United States back in January.

First lady Melania Trump accompanied the president to the pope's funeral.

See photos: Trumps and Bidens at Pope Francis' funeral

President Trump met with Zelenskyy at the funeral in Rome. White House communications director Steven Cheung said the two "met privately today and had a very productive discussion." A spokesman for Zelenskyy said the meeting lasted about 15 minutes.

Former President Biden and former first lady Jill Biden sat farther back among the attendees. Biden, a devout Catholic, had been scheduled to travel to Rome to meet with Pope Francis near the end of his presidency, but canceled the trip to remain focused on devastating wildfires in Los Angeles.

Biden was only the second Catholic president elected to office following John F. Kennedy, who was the first Catholic president after being elected in 1960.