Councillors and officials from Mid Suffolk and Babergh councils are to meet on Monday to try to work out the next steps in merger proposals for the two authorities.

They already share a single administration based in Suffolk County Council’s Endeavour House headquarters in Ipswich.

But plans for a full merger have proved controversial, especially in Babergh, where voters rejected a similar proposal in 2011.

A proposal to move to a full merger without a second referendum lead to the resignation of Babergh council leader Jennie Jenkins last month. Her successor John Ward pledged to hold a referendum when he was elected council leader on Thursday evening.

Originally councillors had hoped that the merger application could be agreed and go to Local Government Secretary Sajid Javid in time for elections to the new authority to be held in 2019.

A public consultation exercise for voters in the two authorities is currently under way and runs until February 5.

However council leaders now recognise that the May 2019 deadline is unachievable and accept that next year’s council elections will be for the existing authorities – although with different ward boundaries and fewer council seats.

There remains deep concern about the proposed merger at Babergh – and some worries among opposition councillors at Mid Suffolk although that council did back the merger proposal six years ago.

Current government rules say councils have to express an interest in merger by 2019. That would not commit them to going through with a merger – but some councillors may be concerned that taking such a step may prove to be an irreversible step along the process.

Mr Ward pledged to work together with Mid Suffolk after being elected. He said: “I am grateful for and humbled by the support of my fellow councillors and I will work tirelessly to be worthy of their trust.

“Babergh faces some big challenges and questions about how we meet the challenge of our central government grant falling to zero and how we take forward our relationship with Mid Suffolk.

“I will be meeting immediately with my fellow members and with our officers to make sure we can answer these challenges, and build the best possible future for everyone in our district.”

Opposition councillors have welcomed the commitment to a referendum. Independent Derek Davis said: “It is only right and proper that a full poll, or referendum, is carried out for the people of Babergh to decide the fate of their district council.

“It took a lot of doing, and it has cost Jennie Jenkins her position as leader, but at last common sense and democracy has prevailed. Let’s hope John Ward sticks to his word.”