Kerry in Afghanistan on key mission to calm election turmoil

U.S. Secretary of State John Kerry arrived in Afghanistan July 11 on a key mission to try to quell tensions over disputed presidential polls which have triggered fears of violence and ethnic unrest.

Kerry, who landed amid tight security on a pre-dawn, unannounced visit, had earlier said Afghanistan faces a "critical moment" as Abdullah Abdullah and Ashraf Ghani wrangle over who will lead the country while international forces prepare to withdraw following more than a decade of war.

Preliminary results from last month's second round run-off have put Ghani in the lead, but Abdullah, who has already once lost a presidential bid, has declared himself the true winner, saying massive fraud robbed him of victory.

The election stand-off has sparked concern that protests could spiral into ethnic violence and even lead to a return of the fighting between warlords that ravaged Afghanistan during the 1992-1996 civil war.

Without backing either candidate, Kerry was to meet Friday with outgoing President Hamid Karzai as well as both presidential hopefuls, U.N. officials and possibly members of the independent election commission.

"A perfect election in these conditions is neither possible nor really the objective," a senior U.S. administration admitted.

The U.S. was "going to push for the very best, most credible, most transparent and most broadly accepted outcome that we can under the circumstances," he told reporters flying in with Kerry from Beijing.

"There are a number of constraints to getting an outcome that would reflect a very exact vote-count... but we can get to a much better outcome than we currently have." Ghani's campaign spokesman Abdul Ali Mohammadi said Kerry was "coming here to solve the election...