The consultation into the draft Black Country Plan ends at 5pm today.
The plan, which will see more than 7,000 homes built on green belt sites across the four boroughs, has sparked a wave of protest since it was published in June, with residents furious that many of the region's precious green fields have been earmarked for development.
Dudley South MP Mike Wood has been campaigning against two proposed developments in his constituency that will see more than 860 homes built on land off Holbeache Lane and at The Triangle, both in Kingswinford.
Petitions against the plans have been signed by more than 6,000 people.
Mr Wood said residents had just hours left to save "our precious local green belt".
He said: "If these 870 homes go ahead as planned, they will destroy our green belt, ruin our wildlife, and add unacceptable pressure to our schools, roads and GPs.
"We do need to build more homes, but they need to be in the right area - we must start with rejuvenating unused land, old factories and industrial sites.
"Our green belt is the lungs of the Black Country - if we lose it, it’s gone for good."
Campaigners in Walsall have called for the consultation period to be extended, arguing that it has been overly complex, inaccessible to many and has not been properly promoted.
To sign the petition to save the Kingswinford sites, visit saveourgreenbelt.uk.