Washington(CNN) Antony Blinken said it is the honor of his life to serve as the top US diplomat after being sworn in as the newest secretary of state Tuesday.
Blinken, a longtime Biden associate, was approved by the Senate with a vote of 78-22 earlier in the day.
"My career has come full circle," Blinken wrote in a tweet Tuesday. "I started at the @StateDept in 1993, and, today, it's the honor of my life to lead the Department's women and men as the 71st Secretary of State."
"I want to thank my colleagues for welcoming me home," he added.
Blinken was sworn in at the State Department by Carol Perez, a career diplomat who is serving as acting under secretary for management. Photos from the event show him taking the oath of office on a copy of the US Constitution.
With Blinken's confirmation, President Joe Biden now has a number of key members of his national security team in place. In addition to national security adviser Jake Sullivan -- who does not require Senate confirmation -- Director of National Intelligence Avril Haines was confirmed on Inauguration Day and Defense Secretary Lloyd Austin was confirmed last Friday.
Blinken's confirmation was welcomed by lawmakers on both sides of the aisle as well as the professional association for the US Foreign Service.
"Leadership of the Department of State, our nation's oldest cabinet agency, represents a great responsibility," the American Foreign Service Association (AFSA) said in a statement. "As we have done for his predecessors, AFSA extends our congratulations and welcome to Secretary Blinken. We wish the Secretary and his team the best of luck in the years ahead. AFSA and its members pledge to work alongside them to strengthen the career Foreign Service and protect and enhance the institution that is American diplomacy."
The 71st secretary of state faces the challenges of restoring America's standing in the world and reinvigorating a department where many felt demoralized under the past administration.
He will also be on the forefront of directing a sharp turn from "America First" foreign policy to one that focuses on multilateralism and coalitions.
During his confirmation hearing last week, Blinken pledged to reengage with Congress on key foreign policy concerns.
He was pressed on Iran and efforts to rejoin the Iran nuclear deal. While Blinken made clear the Biden administration feels the world was safer with the Iran nuclear deal in place, he did not offer specifics on plans to rejoin the Joint Comprehensive Plan of Action (JCPOA), from which the Trump administration withdrew in 2018.
"The President-elect believes that if Iran comes back into compliance, we would too," Blinken said at his hearing a day before the inauguration last week. "But, we would use that as a platform with our allies and partners who would once again be on the same side with us, to seek a longer and stronger agreement. And also, as you and the chairman have rightly pointed out, to capture these other issues, particularly with regard to missiles and Iran's destabilizing activities. That would be the objective."
"Having said that, I think we're a long way from there, we would have to see once the President-elect is in office what steps Iran actually takes and is prepared to take," Blinken said.
On China, he conceded that President Donald Trump "was right in taking a tougher approach to China."
"I disagree, very much, with the way that he went about it in a number of areas, but the basic principle was the right one, and I think that's actually helpful to our foreign policy," Blinken said.
He pledged to restore the agency he now leads, saying he is "committed to advancing our security and prosperity by building a diplomatic corps that fully represents America in all its talent and diversity."
And where his predecessor Mike Pompeo pledged to bring "swagger," Blinken called for "humility and confidence."
"Humility because we have a great deal of work to do at home to enhance our standing abroad. And humility because most of the world's problems are not about us, even as they affect us. Not one of the big challenges we face can be met by one country acting alone -- even one as powerful as the US," he said. "But we'll also act with confidence that America at its best still has a greater ability than any country on earth to mobilize others for the greater good."