Afghanistan''s president says a runoff presidential election must be held as planned next month, despite talk of a power-sharing deal with his challenger to avoid a second vote.

President Hamid Karzai says the second round ballot "has to be held," otherwise "we''ll be insulting democracy." He made the comment on CNN''s "Fareed Zakaria — GPS" program, which aired Sunday.

The runoff was ordered after a U.N.-backed panel voided enough of Karzai''s August votes that he fell below the 50 percent threshold for a first round victory. He now faces Abdullah Abdullah in a Nov. 7 runoff.

Some U.S. officials had hoped the two would reach a power-sharing deal to avoid a second vote.

Karzai acknowledged first round fraud but said the August vote "wasn''t as bad" as claimed.