Ms Williams said ANZ had not identified any alternatives so closure appeared the bank's only option.
Westpac recently announced it was consulting on closing branches in Ranfurly, Te Anau and at the Gardens, North Dunedin. The three are among 19 Westpac branches earmarked for closure around the country.
In Ranfurly, where Westpac is the town's only bank, 300 marched against the proposed closure.
A Westpac spokeswoman yesterday said staff would be advised of the outcome of consultation by the end of the month.
A spokesman for ANZ said the number of customers using the Milton branch had declined to the point ''where we consider it is no longer viable to keep the branch open''.
If the branch closed, all staff would be offered jobs in Christchurch or Dunedin.
Milton would retain a ''Smart'' ATM so customers would have access to cash and could make deposits.
Clutha District Council Bruce ward councillor Gaynor Finch said closing the branch would be ''a step back into the Dark Ages''.
''That will be just horrendous ... it will be dreadful''.
She said the community fought ''hammer, tooth and nail'' with Westpac when it closed its branch, and would again.
She labelled the consultation process in both cases as ''hogwash'' and said both banks had clearly already made their minds up at this stage.
A lot of Westpac customers switched to ANZ when it became the only remaining bank in Milton.
Milton had a large population of elderly who did not use internet or electronic banking and relied on the branch being open.
Many were unable to travel out of the town and she disputed the claim usage had declined.
''This is the last bank for all the people who can't get to any other town in the district.
''If ANZ pull out that's not even going to be funny. How are they going to do their banking?''
