What was supposed to be an open-ended debate on immigration reform stalled on Tuesday when Democrats objected to the Republican’s first amendment, which would punish so-called sanctuary cities.

Minority Leader Chuck Schumer, D-N.Y., blocked a request by Majority Leader Mitch McConnell, R-Ky., to start by debating the sanctuary city language. Without Schumer’s consent, the debate cannot begin until either late tonight or tomorrow morning.