The phrase "to block the project" means to prevent or stop the progress or completion of a particular task or plan.
Sentences with «to block the project»
Don't block this project unless you used beads that can get wet. (thespruce.com)
Is this sufficient to justify blocking a project that comes with so many advantages? (ramblingsdc.net)
Igniting a dialogue on issues related to gentrification, Philly Block Project invites conceptual artist Hank Willis Thomas to engage the community through public forums and photography. (pcah.us)