The Foal Eagle and Key Resolve drills usually start in late February or early March and involve tens of thousands of troops from the two allies, which say they are purely defensive.
Next year's Winter Olympics take place in Pyeongchang in the South from February 9-25, followed by the Paralympics.
According to reports Seoul has asked Washington to delay the drills until after the Games to lower the chances of provocations by Pyongyang.
"The ROK-US alliance continues to discuss the way ahead on the exercises Key Resolve and Foal Eagle, to include the appropriate timing," said US Pacific Command spokesman Commander Dave Benham, Yonhap news agency reported Tuesday.
A statement on the exercises' timing will be issued at the "appropriate time", Yonhap cited Benham as saying.
The comments come after the Financial Times reported that four people familiar with the situation said Seoul had requested the exercises be pushed back until after the Paralympics, which end on March 18.
South Korea's defence ministry spokeswoman Choi Hyun-Soo declined to comment on the report, saying there had been no formal "discussion" between the allies on the issue.
The South's military, police and other units mounted a huge anti-terror drill in Pyeongchang on Tuesday, rehearsing scenarios involving hostages, explosives, vehicle rampages and more.
"After having seen this drill, I am confident that there is nothing to worry in regards to terrorist attacks," said South Korean Prime Minister Lee Nak-Yeon.
"However, accidents happen where we cannot anticipate," Lee added. "Please keep that in mind."
South Korean officials believe that the North's participation in the Pyeongchang Games would guarantee its safety, and hope that the Olympics could serve as a diplomatic opening to defuse tensions.
But Pyongyang boycotted the 1988 Seoul Olympics and has not yet said whether it will take part this time.
The North last month launched an intercontinental ballistic missile capable of reaching the US mainland, the latest in a series of missile tests this year. (AFP)