Russia's Aliya Mustafina will miss the 2011 world gymnastics championships due to a knee injury, her coach said on Monday.

Mustafina, who won two gold medals at last year's world championships, will undergo surgery on her left knee on Tuesday and is expected to be sidelined for between six to eight months, Aleksander Alexandrov said.

The 16-year-old sustained the injury when competing at the European Championships here last Friday.

The 2011 world championships are scheduled to take place in Tokyo in October, but could be rescheduled as a result of the nuclear crisis triggered by last month's deadly earthquake-tsunami in Japan.