Story highlights Current Senate rules mandate that in order to pass cloture on a vote, a 60% threshold is needed

Republicans have instead opted to try to pass tax reform and health care via a process known as reconciliation

Washington (CNN) President Donald Trump urged Republicans Tuesday to change Senate rules to a simple majority vote in order to speed up passage of health care and tax reform bills through Congress.

Trump, back from his first official overseas trip, tweeted that the Senate should switch to "51 votes immediately" adding that "Dems would do it, no doubt!"

Current Senate rules mandate that 60 senators -- three-fifths of the 100-member Senate -- must agree in order to end debate and move forward to a vote on a measure or piece of legislation -- a process known as invoking cloture.

The Senate, however, has invoked the so-called "nuclear option" in the past to get certain nominations -- most recently of note Supreme Court nominee Neil Gorsuch -- through the Senate by a simple majority vote, but there is currently no method for doing so with legislation.

Republicans have instead opted to try to pass tax reform and health care through a process known as reconciliation, which applies to budgetary measures and only requires 51 votes. The process allows lawmakers to vote on critical pieces of the health law without giving Democrats a chance to filibuster, but in turn it places large constraints on members -- including limiting debate to only 20 hours and only using it to change laws that are scored by the Congressional Budget Office, which means those that cost money or are implemented as taxes.

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