Mr Andrews is under renewed scrutiny over his relationship with the volatile leader of the firefighters' union, Peter Marshall, just a month after peace appeared to have finally broken out with a new industrial agreement.

But in a Thursday morning press conference studded with the word "no", Mr Andrews sought to shoot down the speculation that had been running hot since Wednesday's incendiary radio interview Mr Marshall.

"No", there was no secret deal with the union, Mr Andrews  told the gathered media at Moorabbin Oval, and "no", there would be no review of the appointment of the new chief executive of the Metropolitan Fire Brigade that has so incensed the union boss.

And "no", the Premier does not believe Mr Marshall has a secret recording of him that he is using to blackmail him.

Mr Andrews said any pre-election pledges about fire services were already in the public realm.

"We made election commitments which are public and well known because we’ve been getting on and delivering them," Mr Andrews said.

Mr Andrews said the union had been given no assurances that it would be consulted about the MFB's incoming chief, contradicting a statement Mr Marshall issued to UFU members on Wednesday.

"The MFB has run, as we indicated they would, an international process to get the very best CEO," he said.

"That process is run by the MFB, it has been concluded, the best candidate has been chosen and that candidate will take up his position next month and that is the end of the matter."

Firefighters campaigned for Labor during the election.

Opposition Leader Matthew Guy said on Thursday that he had been pressing Mr Andrews for a long time to reveal if he had entered into a secret deal with Mr Marshall.

"They’re similar points to which I have raised in question time to the Premier and the minister for the last three years and that is, 'Is there a deal you did before the election with the United Firefighters Union and if so what’s the details of it?'" Mr Guy said.

When asked on radio station 3AW if he would refer the matter to the state’s anti-corruption watchdog, IBAC, he said the Coalition would consider it.

The opposition promised last year to conduct a royal commission into Victoria’s fire services and the persistent industrial unrest that has gripped it, at a cost of about $10 million.

Mr Guy reiterated that promise on Thursday.

Mr Marshall is furious with the appointment this week of British fire chief Dan Stephens as the new boss of the Metropolitan Fire Brigade, arguing that firefighters have been betrayed.

He said in a radio interview with the ABC's Raf Epstein on Wednesday that Mr Andrews had broken promises he made to firefighters and shattered their faith in his government.

Mr Marshall declined to go into details but threatened to reveal more before the next election in November.

The head of the Metropolitan Fire Board called for calm, arguing that former Merseyside fire chief Mr Stephens will soon demonstrate to all sides why he is the right person to lead Victoria’s fire services out of its state of perpetual industrial conflict.

MFB President Jasmine Doak said she was sorry union chief Mr Marshall was so upset, but she believed in time he would be persuaded that Mr Stephens was a good appointment.

The MFB struck a new enterprise bargaining agreement with the union in early March, ending years of industrial dispute.

The government has estimated the cost of the workplace deal is about $158 million.

The new agreement has a nominal expiry date of May 2019, meaning the next state government will have to resume negotiations soon after November's election.

The generous agreement contains a wide range of perks, including a $1461 relocation allowance and a $1215 second-language allowance.

Firefighters will be eligible for extensive leave entitlements.

Industrial matters related to firefighting have vexed the Andrews government since it came to power.

Legislation to turn the Country Fire Authority into a volunteer-only service and create a new body for paid firefighters from the MFB and CFA called Fire Rescue Victoria, was sensationally blocked in Parliament last month.

The government granted opposition upper house MPs Craig Ondarchie and Bernie Finn a pair on religious grounds during a marathon Good Friday debate, only for them to return minutes before the final vote and defeat the legislation.