Story highlights Democratic Sens. Chuck Schumer and Ben Cardin are opposing the Saudi arms sale

A vote is expected this week to disapprove of the sale of precision-guided munitions

(CNN) Senate Democratic leaders are joining forces with Republican Sen. Rand Paul of Kentucky to oppose a small portion of President Donald Trump's arms deal with Saudi Arabia.

Senate Minority Leader Chuck Schumer announced Monday he was supporting a resolution offered by Paul and Democratic Sens. Chris Murphy of Connecticut and Al Franken of Minnesota to block the sale of $510 million of precision-guided munitions to Saudi Arabia.

Paul and Murphy are expected to force a vote on their resolution -- which is possible under Senate rules for arms sales -- as early as Tuesday, according to Senate aides.

"I will support Senator Murphy's resolution of disapproval," Schumer said in a statement. "The human rights and humanitarian concerns have been well documented and are important: of equal concern to me is that the Saudi government continues to aid and abet terrorism via its relationship with Wahhabism and the funding of schools that spread extremist propaganda throughout the world."

Maryland Sen. Ben Cardin, the top Democrat on the Senate Foreign Relations Committee, came out against the munitions sale to Saudi Arabia last week, citing the Trump administration's decision to sell weapons to Saudi Arabia instead of trying to find a solution to the civil war in Yemen, where the Saudi-led coalition is accused of bombing civilians.

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