Retiring Republican Senator Jeff Flake of Arizona said he would oppose President Donald Trump's request to advance the House Republican's spending bill to avert a partial government shutdown with a simple majority.

"The Senate filibuster is about the only mechanism left in Washington that brings the parties together. Deploying the nuclear option would blow that up. I will not vote to do it," Flake wrote on Twitter on Friday.

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Earlier on Friday, Senate Republicans rejected Trump's suggestion to amend the Senate rules, if necessary, so that Republicans could pass a spending bill that includes $5 billion to build his long-promised wall along the U.S.-Mexico border. Trump urged Senate Majority Leader Mitch McConnell, R-Ky., to "use the Nuclear option and get it done!" in a tweet hours before parts of the government, including the Department of Homeland Security, run out of funding.

The nuclear option would suspend the upper chamber's 60-vote threshold required to pass legislation and allow only a simple majority — just 51 senators or 50, with Vice President Mike Pence serving as a tiebreaker — to pass a bill and send it to the president's desk for his signature and prevent a partial government. McConnell has repeatedly said support does not exist for extending the simple-majority threshold in this case, even among Senate Republicans.

The House of Representatives on Thursday passed a spending bill that would fund the government through Feb. 8, 2019 and includes more than $5 billion for border security. The House bill also includes nearly $8 billion for disaster relief and wildfires. The vote was 217-185 along party lines.

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The House vote failed to break a bitter budget standoff, as Democrats have the Senate votes to block any spending bill that includes funding for Trump's wall — and Trump said he'll veto any bill that doesn't.

If the president and Congress cannot agree on a new government spending package by the Dec. 21 midnight deadline, nine of out of 15 federal departments and dozens of agencies would shutter just three days before Christmas. For now, Congress remains in a race against the clock.