Iranian officials called on “young people” to form human chains around the country’s power plants, in a desperate bid to ward off promised U.S. airstrikes on the country’s power grid.

Tuesday will mark the end of President Donald Trump’s delayed deadline for Iran to open the Strait of Hormuz and strike a deal, or face the destruction of its power plants. With no signs of Iranian and U.S. negotiators nearing a deal, Tuesday will see whether Trump will follow through on his threats. As a last-ditch defense measure, lacking air defenses to resist the strikes, Iranian officials have resorted to calling on the country’s youth to act as human shields, betting that Washington will shy away from extensive civilian casualties.