An "extremely disappointed" NSW Premier Gladys Berejiklian has had a stern word with one of her ministers over an awkward love triangle involving another state Liberal MP and one of the prime minister's staffers.
Racy text messages between Innovation Minister Matt Kean and partyroom colleague Eleni Petinos were revealed on Thursday night when Mr Kean's ex-girlfriend, Caitlin Keage, posted them on social media.
Mr Kean confirmed his two-year relationship with Ms Keage - one of Malcolm Turnbull's media advisors - ended in "spectacular fashion" in late 2017.
Ms Berejiklian, who is in the United States, only found out about the relationship when details were made public this week.
"What I've read this morning is extremely disappointing," the premier told reporters in Washington.
"I'm personally disappointed in him and have told him so, but it is nonetheless a personal matter."
Acting Prime Minister Mathias Cormann says Ms Keage is on leave and "under a fair amount of personal stress".
"I don't really propose to add any further comments to that," he told reporters in Sydney on Friday.
Federal Liberal minister Christopher Pyne described the abrupt breakdown of the relationship as "very sad".
"I know the people involved, they're both friends of mine and it's obviously very upsetting for them all to be involved in this story," Mr Pyne told the Nine Network.
"It's got nothing to do with the prime minister's office, but it's obviously a personal matter and very sad."
