Senate Democrats blocked a must-pass annual defense policy bill from moving forward on Tuesday as they voiced opposition to the Trump administration's handling of the war with Iran.

Members of Congress are drawing lines in the sand on the sweeping defense legislation that requires some Democrats to cross the aisle.

"Simply throwing more money at an out-of-control military operation is not strategy," said Sen. Tammy Duckworth.

President Donald Trump notified Congress of the renewed conflict in a letter to Senate President pro tempore Chuck Grassley (R-IA).