WASHINGTON DC, United States (AFP) — Jimmy Carter brought a fleeting moment of national unity to a divided America Thursday as all five living US presidents gathered for their predecessor’s moving State funeral in Washington’s National Cathedral.

In historic scenes just 11 days before Donald Trump returns to the White House for what promises to be a turbulent second term, Trump shook hands with former President Barack Obama on the country’s day of mourning.

With Carter’s flag-draped coffin nearby, outgoing President Joe Biden and former leaders George W Bush and Bill Clinton were also there to honour America’s 39th commander-in-chief, who died on December 29 at the age of 100.

Biden, 82, delivered the eulogy for his fellow Democrat and old friend, hailing Carter’s “character” and saying that while he appeared to be from a bygone era, “in reality, he saw well into the future”.

He also appeared to deliver a veiled swipe at Trump, the Republican whose racially charged rhetoric and efforts to overturn the 2020 election he has often criticised as dire threats to democracy.

“We have an obligation to give hate no safe harbour and to stand up to… the greatest sin of all, the abuse of power,” said Biden, who will hand over the reins to Trump on January 20.

Carter was widely perceived as naive and weak during his single term from 1977 to 1981, but a more nuanced view has emerged as the years passed, focusing on his decency and foreign policy achievements.

Family members and former political adversaries alike paid emotional tributes to Carter, the oldest ever former US president and the only one to make it to three figures.

One of his grandsons, Jason Carter, described his love of nature in his native Georgia, saying the ex-president “celebrated the majesty of every living thing”.

“He led this nation with love and respect,” Joshua Carter said.

There was even a tribute from Carter’s Republican predecessor Gerald Ford. Ford died in 2006 but left a eulogy for his political rival-turned-friend that was read out by his son Steven.

A second posthumous tribute, from Carter’s vice-president Walter Mondale, was delivered by his son Ted.

Carter’s coffin was earlier transported from the US Capitol, where it had been lying in state, and brought into the immense cathedral by an honour guard of service members in ceremonial uniforms.

Thursday has been designated a national day of mourning in the United States with federal offices closed.

Thousands of mourners had paid their respects in the domed Rotunda after it arrived in the snow-covered Capitol on Tuesday atop a gun carriage.

His carefully choreographed six-day farewell began on Saturday with US flags flying at half-staff around the country and a black hearse bearing his remains from his home town of Plains, Georgia.

The presidential funeral was the first since George HW Bush died in 2018 — and provided a series of unique and sometimes awkward moments as former leaders met.

Obama shook hands, laughed and chatted with his successor Trump, despite the fact that the billionaire built his political movement on questioning whether Obama was really a US citizen.

In the row in front of Trump sat Vice-President Kamala Harris, his defeated rival in the 2024 election.

There was also a brief moment of reconciliation for Trump and his former Vice-President Mike Pence.

The pair met and shook hands for what is believed to be the first time since the 2021 US Capitol riots when Pence refused to back Trump’s false claims to have won the 2020 election.