Barack Obama has offered his condolences to Joe Biden following his devastating prostate cancer diagnosis - after he and Michelle helped to oust him as the Democrat presidential candidate.

"We wish Joe a fast and successful recovery," the president said on Truth Social, after his predecessor was diagnosed with an aggressive form of prostate cancer.

Sympathetic reactions poured in from leaders across the political spectrum Sunday as former President Joe Biden, 82, was diagnosed with an 'aggressive form' of prostate cancer.