Federal CFA intervention a farce: Merlino

Victoria's emergency services minister has described the prime minister's intervention in the CFA dispute as a "farce" just hours after crossbench senator Pauline Hanson pledged her support for the federal government's proposed law changes.

"What we're seeing from the federal government ... has been a political stunt since the beginning and continues to be so," James Merlino told reporters in Melbourne on Monday.

"We've had the farce of the federal employment minister being caught out lying on issues ... and we've had the farce of the Senate inquiry looking at an agreement that was an old version that didn't include the specific provisions to protect the role of our volunteers."

Legislation to amend the Fair Work Act looks set to pass the federal Senate this week after Senator Hanson confirmed she and three fellow One Nation senators would support the government's bill, which Labor and the Greens oppose.

The legislation - which passed the lower house in Canberra in mid-September -aims to protect volunteers by ensuring enterprise agreements can't undermine the ability of emergency service organisations to properly manage their volunteer operations.

National Farmers' Federation president Brent Finlay said passing the Bill was important in guarding against "dodgy deals" designed to overrule state volunteer firefighter laws.

"Passing the bill will give all parties certainty and bring closure to what has become a toxic industrial dispute," he said in a statement.