The 60-year old Carly Fiorina made the announcement Monday via an appearance on the nationwide morning television show "Good Morning America" and social media platform Twitter.

"I am running for President," she wrote, posting a link to her campaign website.

In her first campaign video, she took aim at established US political figures, especially Democrat presidential candidate Hillary Clinton.

"Our founders never intended us to have a professional political class," Fiorina said, after turning off a television set playing Clinton's campaign video.

Fiorina, who was the first woman to lead a US "Fortune 50" company, left HP in 2005 after six years at the helm as the tech company struggled to digest a merger with Compaq. She was an aide in John McCain's 2008 defeated presidential campaign and in 2010 made an unsuccessful bid to unseat long-serving California Senator Barbara Boxer.

Ben Carson launches Republican candidacy

Retired neurosurgeon Ben Carson also formally launched his presidential campaign for the Republican party on Monday in a speech in his native Detroit, after indicating his plans to run in interviews on local television stations over the weekend.

The 63-year-old enjoys support in the party's conservative tea-party movement and has strongly criticized US President Obama's health care law. He served as the head of pediatric neurosurgery unit in Johns Hopkins Children's Center in Baltimore for almost three decades.

So far, US senators Ted Cruz, Rand Paul and Marco Rubio have also officially declared their bids for the Republicans, with former Florida governor Jeb Bush and Wisconsin Governor Scott Walker also seen as likely candidates.

On the Democrat side, Hillary Clinton is the frontrunner, while independent senator #link:18419886:Bernie Sanders is also campaigning to be the Democrat candidate in the White House. The presidential election is scheduled for November 2016.

se/jil (AP, Reuters, dpa, AFP)