Federal Reserve officials were not ready to communicate a timeline for scaling back asset purchases due to high uncertainty on the economic outlook, a record of their June gathering showed, though they did want to nail down a plan in case they have to move sooner.

"The committee's standard of 'substantial further progress' was generally seen as not having yet been met, though participants expected progress to continue," according to minutes from the June 15-16 Federal Open Market Committee (FOMC) meeting published Wednesday. "Various participants mentioned that they expected the conditions for beginning to reduce the pace of asset purchases to be met somewhat earlier than they had anticipated at previous meetings."

The June meeting marked a turn in the central bank's comfort with inflation risks amid heightened price pressures as the economy reopens from the pandemic. But above all, the minutes show the committee had a lot of questions about how soon labor shortages and supply bottlenecks contributing to inflation would resolve.