Conservative GOP leaders in both chambers are brandishing the threat of a potential partial government shutdown to force deep spending cuts in a new round of negotiations on the debt limit and other major budget questions coming up in Congress.

Senate Minority Whip John Cornyn of Texas took on the leader Friday by saying that Republicans frustrated with spending would take a tough line on the prospect of raising the debt limit, a March 1 deadline for automatic spending cuts under the 2011 debt deal (PL 112-25) and the March 27 expiration of the continuing resolution (PL 112-175).