Sefton Central Labour MP Bill Esterson urged Sefton Council's chief executive to ensure that residents' views were heard as part of the Core Strategy consultation.
The council is currently considering resident's responses to the Core Strategy consultation document.
Depending on the 15 year future strategy chosen by Sefton Council, parts of Sefton's greenbelt could be built on.
Hundreds of people have contacted the Labour Sefton Central MP calling for the greenbelt to be protected.
During a meeting with Sefton chief executive Margaret Carney, Bill Esterson told the council boss that she has a responsibility to ensure that residents' views were considered.
Bill said: "I had a full and frank meeting with Margaret Carney when I raised some of the major issues brought to me by my constituents - primarily the Core Strategy and the need to protect the greenbelt and greenspace.
"I urged her to ensure that her officers fully considered each and every response from residents concerning the Core Strategy.
"Residents across the constituency and across the borough are speaking with one voice - protect the greenbelt and protect our greenspaces."
During the meeting, Bill also urged the chief executive to back the campaign to protect the borough's greenbelt and greenspaces.
Bill said: "Mrs Carney clearly knows the level of opposition to building on the greenbelt and greesnpaces in Sefton.
"I strongly urged her to ensure that she backed the residents of Sefton.
"She made very clear to me that the council would fully consider all of the views submitted as part of the Core Strategy consultation. If that is the case, then there is only one conclusion officers can come to - no building o the greenbelt."