Afghanistan election talks break down: report

Afghan President Hamid Karzai speaks at a news conference in Kabul October 11, 2009.

WASHINGTON (Reuters) - CNN, quoting an unidentified Western source, said on Friday election talks between Afghan President Hamid Karzai and his rival Abdullah Abdullah had broken down and that Abdullah would likely announce he will boycott the November 7 run-off vote.

Abdullah, a former foreign minister, was likely to make the announcement this weekend, CNN said, citing the source who it said was close to the Afghan leadership.

The run-off between Karzai and Abdullah was triggered by a U.N.-led investigation into the first round of voting in August that found widespread fraud in favor of Karzai.

It comes as U.S. President Barack Obama weighs whether to send thousands more troops to Afghanistan, where violence this year has reached its worst levels since the Taliban was ousted by U.S.-backed Afghan forces in 2001.

Security is a major concern for the run-off, which the Taliban has vowed to disrupt. That was underlined by a suicide attack this week on a guest-house used by the United Nations in Kabul in which five foreign U.N. staff were killed.

(Writing by Peter Cooney; Editing by John O'Callaghan)