A senior CFMEU official has questioned the looming merger of Australia’s biggest unions.

­Michael Ravbar, the Queensland construction division secretary of the Construction Forestry Mining and Energy Union, expressed some concerns about the merger in documents filed in June.

He has now spoken about them publicly.

Mr Ravbar told News Corp reporters that the merger with the Maritime Union of Australia should not be a priority for the CFMEU.

“There is [already] too much duplication in the union,” he said.

“Sometimes the thinking is that bigger is better, but I don’t think that is always the way.”

Officials are pushing to have the merger ­approved this year.

“I think there are other issues that are more important; we need to focus as a union on a number of these other issues,” Mr Ravbar said.

“I don’t think the timing is quite right.”

Reports say the MUA was not impressed by the CFMEU’s decision last month to split from the Queensland Council of Unions.

The CFMEU’s construction and mining divisions broke links with the QCU, accusing it of not pressuring the Palaszczuk government for industrial manslaughter laws, which the Government had pledged to ­introduce this year.

MUA state secretary Bob Carnegie says the CFMEU’s split with the QCU meant the merger proposal may have to be reconsidered.

“The MUA are still an affiliate of the QCU,” he said.

“Are we going to have a merger with the mining and construction divisions of the CFMEU who aren’t affiliated with the QCU? How does that work?”

Mr Carnegie said the CFMEU’s decision to split with the QCU did not make sense.

“The QCU have worked night and day to get the ALP government to ­introduce industrial manslaughter ... law,” he said.

“If it is the government under pressure, then it makes more sense to move on the ALP, not the QCU.”