Campaigners wanting to see the community feeding team continue in Stoke-on-Trent will present their case to the city council later.
The authority commissioned service was provided by Midlands Partnership NHS Foundation Trust, but the contract was not renewed when it came to an end on 31 August.
The city council say the decision was made because the team had failed to improve breastfeeding rates.
Volunteers, such as those who run the Breasts and the City group, say there was no consultation on the plans - and they believe they are now expected to offer help to mums, even though they are not medically qualified.
They also say that listening workshops that took place in August, to look at what other services are in place and to plan for the future, should have been held months ago.
Breasts and the City group volunteer Laila Khawaia with peer support volunteers Eleanor Gratton and Melinda O'Brien
An epetition launched in July, calling for a rethink of the plans, was signed by 5,327 people.
Under city council rules, any petition containing 5,000 or more signatures will see the lead petitioner be allowed five minutes to speak on the issue, which can then be debated by the full council.
This will take place at a city council meeting this afternoon (5 September).
Peer supporter Meg Jorsh will be addressing councillors.
She said: "It is a very important public health issue.
"One of the things I am going to stress in my speech is that Stoke-on-Trent has one of the highest infant mortality rates in the country, so there is clearly a problem with the health of our babies.
"There is nothing better we can do to improve their health than breastfeeding.
"It is something that is natural, but that doesn't mean it is not a skill that needs to be learned.
"Trying and not being able to breastfeed is strongly connected to postnatal depression.
"The service has already closed, but we want them to find emergency funding to reopen it until they can properly scrutinise the decision - and come up with a suitable replacement service if it must close."
Ahead of the end of the current contract for the CFT, Dr Paul Edmondson-Jones, Stoke-on-Trent City Council’s director of adult social care, health integration and wellbeing, said: “Breastfeeding makes a key contribution to a child’s health and development – and also has many benefits for mothers – and we want to see the best support available in order to increase its uptake within the city. Unfortunately, the current service has not been giving us value for money. Breastfeeding rates have not changed over the past three to four years, and the service has only been reaching about half the new mothers in the city.
“This is why we took the decision not to renew the contract with the Community Breastfeeding Team, and this service will come to its natural end on August 31.
“Previously, we engaged with both professionals and service users, but we recognise now that this was not as effective as we would have wished.
“We are currently working with the community in the form of proactive engagement workshops to develop ideas, with a view to making sure future support is available that makes the best use of our available resources.”