Senate leaders are sounding the alarm over the possibility that a critical intelligence surveillance tool could lapse temporarily Friday unless senators reach an agreement to speed up the passage of the bill that would renew the program for two years.

Section 702 of the Foreign Intelligence Surveillance Act, which authorizes the government to spy on foreigners abroad, is set to expire on Friday, and top lawmakers on both sides of the aisle are urging their colleagues not to engage in a battle over amending the House bill.