Carwyn Jones has failed to be renominated as First Minister at the first attempt after a challenge by Plaid Cymru's Leanne Wood.
The vote on whose name to submit to the Queen was tied 29-29.
Deputy Presiding Officer Ann Jones was not allowed to vote but all other Labour AMs backed their leader, as did the Liberal Democrat Kirsty Williams.
Leanne Wood was backed by all other opposition AMs, apart from the Presiding Officer, Elin Jones, who like her deputy did not vote.
The decision has now been postponed to the Assembly's next sitting.