In a statement, a spokesperson for China's foreign ministry said "preliminary verification" had indicated that two Chinese citizens were "unfortunately killed in the accident".

"China expresses deep condolences to the victims and extends sincere sympathies to the bereaved families," the spokesperson said.

"China has requested the US side to promptly update it on the progress of the search and rescue operations, swiftly clarify the cause of the accident and properly handle follow-up matters," they added.

Beijing did not share further details about its nationals killed in the crash, in which 67 people died.

Over 40 bodies had been recovered as of Thursday evening, according to US media reports.

Among those on the airliner were several US skaters and coaches, US Figure Skating said.

Officials in Moscow also confirmed the presence of Russian couple Evgenia Shishkova and Vadim Naumov, who won the 1994 world pairs title.