washington secretary state rex tillerson visit mexico week along homeland security secretary john kelly discuss issue include border security southern neighbor amid fray relations new u.s. president donald trump tillerson kelly meet mexican president enrique pena nieto top mexican officials two-day visit wednesday thursday state department say statement discuss border security law enforcement trade state department say feb. 22-23 visit come amid tensions unite state mexico since trump take office jan. 20. trump vow build wall u.s. southern border slap hefty tax mexican-made goods enter country pull trade deal mexico renegotiate benefit unite state pena nieto cancel plan january meet two leaders washington trump say counterpart attend unwilling pay wall despite tensions senior mexican american military interior officials speak month sign communication remain open two countries top u.s. diplomat security chief visit mexico wednesday