WASHINGTON, D.C. - Congress is still debating how much authority the Trump administration should have over future military action against Iran.

House and Senate Democrats are separately drafting a War Powers Resolution that would limit the president’s military authority, and require congressional approval in the future. A vote is expected in the House by the end of the week, according to house speaker Nancy Pelosi. A vote in the Senate could depend on the upper chamber’s impeachment trial timeline, which has yet to be determined.

“I don’t think the president needs a permission slip from Congress when he’s acting in a way to keep Americans safe,” said Sen. Pat Toomey (R-Pa.), who defended the Trump administration’s drone strike over the weekend that killed Iranian Maj. Gen. Qasem Soleimani.

But for some lawmakers, including Toomey, reining in executive power on this issue isn’t as critical as it is in other areas. Toomey has been critical of Trump’s stance on trade. The Pennsylvania senator is the only open “no” vote on the U.S.-Mexico-Canada Agreement. (However, fellow Sen. Bill Cassidy (R-La.) joined Toomey in voting against the deal during a Senate Finance Committee markup on Tuesday. Together, they are the only two GOP senators opposed to the deal that attempts to modernize the 1990s-era North American Free Trade Agreement.)

When asked why not push for more congressional authority on military operations if he is open to reining in executive overreach on trade policy, Toomey said there is a big difference between the two issues.

“Part of the responsibility of the Commander-in-Chief is to keep Americans safe when he can,” Toomey explained. “Soleimani was clearly a threat to American lives.”

But some senators are worried Trump’s actions could lead the United States into further military action, possibly even war, if Congress doesn’t check the executive branch now.

Sen. Kirsten Gillibrand (D-N.Y.) is urging the Senate to consider her legislation that would reform the 1970s-era War Powers Resolution. First introduced in November, her proposal would re-write a law passed after the September 11th attacks that currently gives presidents more power to pursue military operations without congressional approval.

Gillibrand’s proposal would repeal the 2001 and 2002 laws, known as the Authorization for Use of Military Force, and require the president to provide Congress with a clear objective for military action. It would also authorize military action for only two years.

“I’m deeply concerned that Congress has lost our authority and ability to decide when to declare war,” Gillibrand said in November. “The truth is that constant deployment and mission creep is not what the Framers intended.”

“I think it’s very clear that the president made this decision out of a menu of options that have been presented to him, and he picked the one that was probably going to lead to the most consequential kinds of events that we’re now seeing,” said Sen. Mazie Hirono (D-Hawaii).

On Wednesday, senators are scheduled to receive a detailed classified briefing about last week’s attack, Toomey said.