Caretaker Asian boss steps aside from election

"He's not running. He has decided after long and careful thought," said the source close to Zhang. "He doesn't want the AFC to be split for the next two years."

The 61-year-old from China took the reins in June 2011 after former president Mohamed bin Hammam was banned from football activities over bribery accusations which he denies.

Zhang had previously been seen as the favourite to win the job full-time at elections in early May, and had spoken of his wish to bring greater transparency to the regional body.

Thai football chief Worawi Makudi, a bin Hammam ally, has already thrown his hat into the ring, along with Bahrain's Sheikh Salman bin Ibrahim al-Khalifa. The election winner will be in charge until 2015.

"The member associations are split not in half, but in several parts," the source said. "It's his (Zhang's) wish that the football family can get together, back to unity and solidarity."