The Cootamundra-Gundagai Regional Council will write to the minister inviting her to come and discuss issues that have emerged from the amalgamation, in particular whether it has been cost-effective.

Ms Hancock, MLA for the South Coast since 2003, has been in the ministry since the re-election of the Berejiklian government in April, previously serving as Speaker for eight years.

A resolution at the June council meeting to ask her to review the merger followed discussion by Mayor Abb McAlister of his attendance at the NSW Country Mayors' Association meeting in Sydney in May, at which Ms Hancock gave a speech.

After her speech, Cr McAlister asked the minister "whether, as in business, if you make a decision to do something such as the mergers, do you come and have a look to see if they've been successful or not?"

"At the present time - and I'm sure we'll all admit it here - it's going to cost a lot more money to run two councils together as two councils apart," Cr McAlister said.

"I said it was a very good council, we work well together, but we've got to face facts.

"Her answer was yes, I know, and her door was open to discuss.

"You'd just like to think it's like in business, if you change your business or you go this way, you sit down after two or three years and say 'well is it working?'.

"Do we still go this way, or make changes, or forget it?"

Another question raised at Mayors Association meeting was about equalising rates between merged councils.

Mayor Ken Searles, Dubbo, said the equalising should take place over three or four years.

Cr McAlister disagreed, saying if should be done in one year so that if people asked about it the council could point to the merger as the reason behind it.