US Secretary of State John Kerry arrived in Kabul today to cut a deal between Afghanistan’s rival presidential candidates as their election dispute risked spiralling out of control.

Mr Kerry met the two challengers — former finance minister Ashraf Ghani Ahmadzai and former foreign minister Abdullah Abdullah — as well as current President Hamid Karzai.

His objective was to convince both candidates not to claim victory prematurely and to persuade them to set up a temporary shared government until the United Nations can conduct an audit of extensive electoral fraud allegations.

“We are in a very, very critical moment for Afghanistan,” Mr Kerry said on meeting UN representative Jan Kubis. 

“Legitimacy hangs in the balance. The future potential of the transition hangs in the balance.”

Mr Kerry said that Washington wanted a process that confers legitimacy on whoever emerges as rightful leader, “but I can’t tell you that’s an automatic at this point.”