With President Donald Trump signaling he may declare a national emergency to fund his proposed border wall, he’s meeting opposition from a powerful member of his own party: Senate Finance Committee Chairman Chuck Grassley.

“ ‘I think it’s a bad precedent and it contravenes the power of the purse that comes from the elected representatives of the people.’ ” — Sen. Chuck Grassley

The Iowa Republican, who took the top spot on the finance panel on Wednesday, spoke to CNBC as the administration was reportedly mulling the diversion of disaster relief funds to build Trump’s wall. Federal law allows the president to divert such funds.