Sefton Central Labour MP Bill Esterson said he has been contacted by a growing number of people from Formby who are concerned that the town is being split in two by the boundary changes.
The Boundary Commission last week announced that Sefton Central will become the Maghull constituency, with the loss of Harington Ward in Formby and Blundellsands in Crosby and gaining St Oswald's Ward and Kirkby's Shevington, Park, Whitefield and Northwood wards.
As part of the changes, Harington will go to Southport and Blundellsands to Bootle.
After fully assessing the Boundary Commission's proposed changes Bill said he was concerned that Formby was being split in two.
Bill said: "I am very familiar with the concerns of the Formby community. Week in and week out I can be found knocking on doors in this community to listen to those concerns and the viewpoints of people who live here to feed back to Parliament and also to act upon locally.
"As MP for the town I see that as one of my primary responsibilities. If the worse comes to the worst and Formby is split in two, I will still fight for the people in the area which is my responsibility, but my concern is that the area which falls within Southport will not get the same level of commitment from the incoming MP.
"The community of Formby is one of the most historic communities in the region and it is simply bizarre to think that it could be arbitrarily split up by these boundary changes.
"Formby needs to remain together and that is what I am calling for."
The Boundary Commission's recommendations are currently open for public consultation, but there is only a short window for objections.
Bill said: "I am making my feelings very clear on my wish to keep Formby together.
"I can't imagine that splitting Formby in two is in anyone's interests apart from to enable this Tory-led government to instigate changes to the current boundaries to reduce the number of Labour MPs in this region. This is clearly undemocratic.
"These changes are going to cost a lot of money and the government claims it is saving money don't bare scrutiny.
"At the same time of getting rid of 50 MPs they have increased by the number of peers in the Lords by 170. This exposes the real purpose of these changes as the Conservatives gerrymander the constituency boundaries to safeguard the Tory powerbase."
"If these changes are introduced, I can envision incidents where I as MP for one side of a road in Formby will be working on an issue for one group of people, while the neighbours on the other side of the road will have to contact the MP for Southport.
"While the Boundary Commission is satisfying the strict guidelines laid out by the government in terms of sticking to the population requirements for they are doing so at the expense of communties like Formby."