<P> The following officials hold positions that are considered to be Cabinet - level positions . Cabinet - level officials attend Cabinet meetings, but are not official Cabinet Members: </P> <Table> <Tr> <Th_colspan="3"> Cabinet - level Officials </Th> </Tr> <Tr> <Th> Office </Th> <Th> Incumbent </Th> <Th> Term began </Th> </Tr> <Tr> <Td> White House Chief of Staff (Pub. L. 76--19, 53 Stat. 561, enacted April 3, 1939, Executive Order 8248, Executive Order 10452, Executive Order 12608) </Td> <Td> John F. Kelly </Td> <Td> July 31, 2017 </Td> </Tr> <Tr> <Td> Trade Representative (19 U.S.C. § 2171) </Td> <Td> Robert Lighthizer </Td> <Td> May 15, 2017 </Td> </Tr> <Tr> <Td> Director of National Intelligence (50 U.S.C. § 3023) </Td> <Td> Dan Coats </Td> <Td> March 16, 2017 </Td> </Tr> <Tr> <Td> Ambassador to the United Nations (22 U.S.C. § 287, Executive Order 9844, Executive Order 10108) </Td> <Td> Nikki Haley </Td> <Td> January 27, 2017 </Td> </Tr> <Tr> <Td> Director of the Office of Management and Budget (31 U.S.C. § 502, Executive Order 11541, Executive Order 11609, Executive Order 11717) </Td> <Td> Mick Mulvaney </Td> <Td> February 16, 2017 </Td> </Tr> <Tr> <Td> Director of the Central Intelligence Agency (50 U.S.C. § 3036) </Td> <Td> Mike Pompeo </Td> <Td> January 23, 2017 </Td> </Tr> <Tr> <Td> Administrator of the Environmental Protection Agency (5 U.S.C. § 906, Executive Order 11735) </Td> <Td> Scott Pruitt </Td> <Td> February 17, 2017 </Td> </Tr> <Tr> <Td> Administrator of the Small Business Administration (15 U.S.C. § 633) </Td> <Td> Linda McMahon </Td> <Td> February 14, 2017 </Td> </Tr> </Table> <Tr> <Th_colspan="3"> Cabinet - level Officials </Th> </Tr> <Tr> <Th> Office </Th> <Th> Incumbent </Th> <Th> Term began </Th> </Tr>

Who is considered the most powerful official in the senate