Is Faskh of Nikaah based on Ijma'

Am I correct in understanding that Fasakh as understood by the Ahlus Sunnah wal Jamah is based on the ijma practice of the Sahaba (Radiyallahu Anhu)? Mufti I am very staunch that we follow orthodox Fiqh and I am not seeking to cause problems, instead I am trying to defend particularly the Shafi mazhab against people who argue that they can make ijtihad and grant a fasakh as equal to a Talaq (i.e. without any conditions at all).

And as much as all sunni Ulama reject this assertion of theirs I would like to understand what the Sunni view is based on, please.