In a highly significant move, a “fired up” President Obama took to the stage in North Carolina to offer his unequivocal backing to his former rival turned ally, Hillary Clinton. Pragmatic partnership has replaced the bitterness and distrust which characterised the 2008 presidential campaign.

They strode on stage under the banner “Stronger Together”. They held hands, arms raised up high, in a sign of unity. She wore a vibrant fuchsia jacket, he was in a white shirt, his sleeves rolled up. They were “fired up, ready to go”, ready to make their case for a Clinton presidency, one that would build on the Obama legacy.

It was the strongest moment yet in Hillary Clinton’s campaign and a mesmerising image of two former rivals turned allies, their political destinies now deeply intertwined.

She spoke first, as he sat on a stool behind her. They paid tribute to each other, their work, leadership and most importantly for her, their character.

“He’s a statesman, leading not just our country but the entire world,” she said. The president later said: “My faith in Hillary Clinton has always been rewarded.”

The morning had been overtaken by the drama of the FBI’s final findings after months of investigation into Clinton’s unusual private email set-up as secretary of state. There would be no charges, but the FBI said she had been ”extremely careless”, leaving a heavy cloud hanging over her campaign.

Neither Mrs Clinton nor the president addressed the controversy in their remarks, focusing on the unique and unlikely relationship they had forged.