Vice-President Joe Biden says he does not know if he has the “emotional energy” to run for president in 2016.
Joe Biden, 72, said at a foreign policy lecture in Atlanta: “I can’t look you straight in the eye and say now, <<I know I can do it>>.”
The Democrat lost his son, Beau Biden, to cancer earlier this year.
The media have watched and waited for weeks for a hint that Joe Biden will challenge the Democrat front-runner Hillary Clinton.
He told those gathered in Atlanta: “The most relevant factor in my decision is whether my family and I have the emotional energy to run. The factor is, can I do it?
“The honest to God answer is I just don’t know.”
Some Democrats have urged Joe Biden to run as Hillary Clinton’s campaign appears to be struggling with questions over her use of emails when she was Secretary of State.
Joe Biden failed in his bids for the White House in 1988 and 2008 before becoming Barack Obama’s running mate.