Elizabeth Warren, the Democratic senator from Massachusetts, said U.S. strikes on Iran over the weekend were an "act of war" that President Donald Trump did not have the authority for under the Constitution.

President Donald Trump's strike against Iran will be met with pushback on Capitol Hill this week as some lawmakers argue the military action was unconstitutional. There are several bipartisan resolutions that could receive a vote in coming days that may put some lawmakers in uncomfortable positions as they consider whether Trump ignored the role of Congress in striking Tehran.

The Israeli prime minister had set in motion plans to attack Iran long before President Trump began efforts to resolve nuclear concerns through negotiations.