Acting Victorian Premier James Merlino is facing pressure to address allegations that one of his MPs engaged in improper behaviour, including claims a parliamentary office was used for sex.
The government has raised concerns about the accusations with Speaker Colin Brooks, with a spokeswoman saying this was "the appropriate avenue to make or refer complaints about MP conduct".
However Mr Merlino is expected to be asked about the allegations directly when he fronts the media later on Sunday morning.
The claims were first raised in March, with News Corp reports emerging on Saturday that a government MP allegedly had sex in a parliamentary office last December.
"This kind of behaviour is completely inappropriate and falls well short of community standards," the government spokeswoman said.
Opposition leader Michael O'Brien also planned to speak further on the issue on Sunday afternoon, his office said.
"The Labor Party are very good at saying that the standard you walk past is the standard you accept," Mr O'Brien told reporters on Saturday.
"So the question for the acting premier is does he approve of what this Labor MP has been doing in his office and will he come clean and name this person because I think Victorians have a right to know ... (it's) not what people expect to go on in Parliament House."
Mr Brooks is leading a cross-party process to develop a new framework for MP conduct intended to include new and independent avenues for complaints to be made.
Ministerial staff are able to raise formal or informal complaints with policies in place outlining the processes involved.
Any staff member who wishes to make a complaint is encouraged to do so with an undertaking that each one will be treated seriously and actioned appropriately.
