Former US vice-president Biden to contest Presidential polls

Former Vice President Joe Biden formally joined the crowded Democratic presidential contest on Thursday, betting that his working-class appeal and ties to Barack Obama's presidency will help him overcome questions about his place in today's increasingly liberal Democratic Party. He made his announcement in a video posted on Twitter.

Washington: Putting an end to month long speculation, former US vice-president Joe Biden on Thursday announced his candidacy for the presidential nomination for 2020 elections.

"The core values of this nation ... our standing in the world... our very democracy ... everything that has made America -- America -- is at stake. That's why today I'm announcing my candidacy for President of the United States," Biden tweeted, along with the campaign video.

The 76-year-old will be competing with 20 other candidates including heavyweights like Bernie Sanders and Elizabeth Warren to win Democratic nomination.

In a video message titled "America Is An Idea", Biden began his address by recounting an incident in 2017 when a rally in Charlottesville, Virginia by "neo-nazis" and "white supremacist" turned violent, leading to the death of three people.

His announcement signalled that the core message for his campaign would be that Donald Trump's presidency "has left the country in a state of crisis".

"Everything that has made America America is at stake," Biden said. "That's why today I am announcing my candidacy for president of the United States."

This will be Biden's third attempt after two unsuccessful campaigns in 1998 and 2008. In 2008, he joined the Obama ticket as candidate for vice-president. He did not contest in 2016 after his son, Beau Biden, died of brain cancer, reported The Hill.

Democrats will question him for his vote to authorise the invasion of Iraq 2002. He has been accused by women of inappropriately touching them.

Biden is also likely to face questions about his age. If he wins, he would be the oldest person to occupy the oval office - at 78 years of age.

Biden was first elected to the US Senate at the age of 29.