Influential U.S. Senator Max Baucus is reported to have been chosen as Washington's next ambassador to China, filling one of America's most complicated diplomatic posts at a time of increased tension with Beijing.
Senate aides say President Barack Obama could announce as soon as Thursday the nomination of Baucus, a veteran lawmaker with a record of taking a tough stance against controversial Chinese trade practices.
The 72-year-old senator from the northwest state of Montana, who refused to comment on the reports, would be tasked with helping execute the White House's economic and security rebalancing toward Asia.
Baucus earlier this year announced he would retire from the Senate at the end of 2014. He currently serves as the chairman of the Senate Finance Committee, which deals with tax and other revenue issues.
The Senate would have to confirm the nomination. Current Ambassador Gary Locke announced last month he would step down as ambassador to spend more time with his family.
Jon Huntsman, who preceded Locke as U.S. ambassador to China, praised the reported nomination, telling Buzzfeed that Baucus' influence in the U.S. Congress would resonate well with Chinese leaders.
U.S.-China relations have been strained by Beijing's recent declaration of an Air Defense Identification Zone in the East China Sea, which covers territory also claimed by U.S. ally Japan.
The U.S. has flatly rejected the zone, flying two B-52 bombers on training missions through the zone in defiance of Chinese demands that they identify themselves and submit their flight plans.
China is also skeptical of the U.S. "pivot" toward Asia, viewing it as an attempt to contain its rising influence. The White House denies this is the case.
The two countries have also quarrelled over trade issues, such as the alleged Chinese theft of U.S. trade secrets and widespread Chinese hacking against U.S. commercial and government targets.
As chair of the Senate Finance Committe, Baucus has been one of Congress' main supporters of a more forceful U.S. stand against what he considers unfair Chinese trade practices.
There has been no reponse from Beijing on the reported nomination.