A continued tough U.S. stand on trade and diplomacy with China was confirmed with the swearing-in of Avril Haines as the Director of National Intelligence (DNI) by Vice President Kamala Harris Thursday.

"Earlier today, I swore in our first cabinet member, Avril Haines, after her confirmation by the Senate last night," tweeted Harris. "As the Director of National Intelligence, Director Haines will be dedicated to keeping the American people safe."

During her confirmation hearing before the Senate Select Committee on Intelligence, Haines said the U.S. must take an "aggressive stance" toward the threat posed by China's global aggressiveness.

She is joined in this view by the two top U.S. national security leaders: Secretary of Defense nominee Gen. Lloyd Austin and Secretary of State nominee Anthony Blinken. Both Austin and Blinken are expected to be confirmed in their positions by the Senate by next week.

Asked by Warner if China under the rule of the Communist Party of China is an adversary of the United States, Haines replied: "When it comes to espionage ... they are an adversary."

She pledged to counter China's "illegal, unfair, aggressive actions." She also promised to provide training for local officials to educate them on China's influence operations.

"Serving in this role is the honor of a lifetime," said Haines in a statement later.

The Senate the day before approved Haines' appointment by an 84-10 vote. All the "no" votes came from Republicans. Democrats and leading Republicans, however, later issued statements praising Haines.

"After being deliberately undermined for four years, the Intelligence Community deserves a strong, Senate-confirmed leader to lead and reinvigorate it," said Sen. Mark Warner, a Democrat from Virginia, who will chair the intelligence committee in the new Senate.

Republican stalwart Sen. Marco Rubio from Florida, the acting outgoing chairman of the intelligence committee, said he's "pleased my Senate colleagues joined me in swiftly confirming Director Haines to this important post."

Haines previously served as Deputy National Security Advisor and Deputy Director of the Central Intelligence Agency (CIA) in the Obama administration. She was the first woman to hold this key position.