Hillary Clinton was publically sworn-in as US Secretary of State by Vice President Joe Biden at a ceremony held at Foggy Bottom in Washington.

Hillary's husband and former US President Bill Clinton and her daughter Chelsea were also present at the ceremonial swearing in ceremony on Monday, which included several former Secretaries of States and Congressional leaders.

She is the 67th Secretary of State. Hillary replaces Condoleezza Rice of the previous Bush Administration.

Speaking on the occasion, Biden said he is confident that with Clinton as Secretary of State, the Obama Administration would be able to achieve its foreign policy goals in challenging times.

"In selecting Senator Clinton for this critical task, I think the (US) President selected a person of unrivaled talent and experience," Biden said.

"While serving as the first lady and as US Senator, she's already represented the US in over 80 countries, and is equally at ease in the great diplomatic halls of Europe as she is in small villages in Africa," he said.

"The national security challenge before this administration is great. We are engaged in two wars. We face a continued threat of terrorist attack by Al-Qaida and its allies. We face numerous transnational threats, including the spread of lethal weapons, climate change, disease, and that require common action," the Vice President said.

"To meet these threats, our military might is absolutely necessary. But, to state the obvious, it is not sufficient. We must use the totality of America's strengths, starting with our diplomacy and the ideas and ideals that inform it," Biden said.