Speculation rife over Biden joining 2016 US presidential race

Speculation is rising that Vice President Joe Biden is close to a decision on entering the 2016 US presidential race even as the White House has been silent and President Barack Obama evaded queries on the issue.

The immediate provocation appeared to be an email written by Biden's close aide Ted Kaufman to his supporters that the vice president's campaign would be "optimistic", "from the heart" and unscripted.

The email was written late on Thursday and on Friday the International Association of Fire Fighters informed Biden that its union will endorse him if he enters the race.

"If he runs, he will run because of his burning conviction that we need to fundamentally change the balance in our  economy and the political structure to restore the ability of the middle class to get ahead," Kaufman wrote according to multiple media reports.

According to the Wall Street Journal, Biden is expected to announce in the coming days whether he will enter the presidential race and, at this point, signs point to him running for the Democratic nomination, people familiar with the matter said.

"Mr Biden could still pull back, however, if he concludes he is too shaken by his son's recent death to mount a campaign. Another consideration for Mr Biden: the fortunes of frontrunner Hillary Clinton," the daily said referring to the massive hand in cash that Clinton now has.

Obama deflected questions on this.

"I am not going to comment on what Joe is doing or not doing. I think you can direct those questions at my very able vice president," he said at a White House news conference.

"I think that the vice president, like every other candidate, makes their own decisions about these issues and they'll have to figure out what makes sense for them," Obama said and declined to name his favourite candidate.

A day earlier, Biden had refused to entertain any such questions from reporters.

However, CNN said Biden has personally made a series of calls this week to Democratic strategists from Iowa, New Hampshire and South Carolina, asking a final round of detailed questions about how -- not whether -- to launch a 2016 presidential campaign.

"One senior party official said the announcement is expected in the next three days, while other Democrats say Biden may wait for a week or more. He will reveal his decision before the month's end," CNN reported.