Police have concluded no offence was committed after a Victorian Liberal MP alleged she was assaulted by a colleague.

Liberal Moira Deeming had accused former party leader Matthew Guy of assaulting her during a function in May.

CCTV footage of the incident that has been released appeared to show Guy putting his hand on Deeming’s upper back as they leant in to talk to one another.

Victorian Liberal leader Jess Wilson had confirmed the matter was being investigated.

“Like every other Victorian, the parties involved deserve due process, the presumption of innocence and their privacy respected while this is investigated,” she said in a statement on Thursday.

Guy, a former state Liberal leader, and Deeming have both been contacted for comment.

The Age has reported that Guy “vehemently denied to colleagues that anything untoward took place”.

Late on Thursday, Victoria Police released an update.

“Following a thorough investigation, it has been determined there was no offence detected,” they said.

Police said the incident occurred on May 23 and was reported to them on June 16.

“The woman did not require medical attention,” they said, adding that “investigators have engaged with the woman who made the report”.

Wilson said her focus remained on issues important to voters and earning their trust ahead of the November state election.

In the CCTV footage, Guy is seen seated at a table and talking with Deeming and another man.

Guy appears to place his hand on Deeming’s upper back or shoulder area and pull her in to say something before making a similar gesture with the man.

State Attorney-General Sonya Kilkenny asked what and when Wilson knew about the allegation, what she had done and whether it was appropriate for MPs to remain in the partyroom when they were the subject of a police complaint.

“An alleged assault by one Liberal member of parliament against another Liberal colleague — they’re serious questions that the Liberal leader Jess Wilson needs to come and answer,” Premier Jacinta Allan said earlier on Thursday.

The allegation comes five months out from the state election, where the state Coalition faces a three-term Labor government and a surging One Nation.

-AAP