Watch: White House's Spicer gives briefing amid new Syria sanctions, looming government shutdown

Mnuchin: New sanctions against Syrian scientists

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White House press secretary Sean Spicer held his daily briefing Monday ahead of this week's possible fight over keeping the government open.

Congress returns from a recess this week with only a few days before government funding ends on Friday. The White House has complicated matters by insisting that a funding bill has money for the construction of a wall on the U.S.-Mexico border and pushing for it to withhold some subsidies for the Affordable Care Act.

Spicer said negotiations are ongoing among congressional leadership about some of those provisions. He declined to provide updates on the status of specific funding issues.

Treasury Secretary Steven Mnuchin also appeared at the briefing after his department unveiled sanctions against 271 individuals in response to an apparent chemical attack in Syria earlier this month.

Last week, President Donald Trump put more pressure on what will already be a difficult legislative week by saying he wanted to Congress to vote on a revised plan to replace the ACA. However, he said Friday that "it doesn't matter" if a health-care vote takes place this week.

Trump also promised to make a "big announcement" on his tax reform proposal on Wednesday. However, he did not say how many details of the plan would be released.

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