Reuters reports, U.S. President Donald Trump is expected to formally announce a review of vehicle fuel efficiency rules locked in at the end of the Obama administration when he meets with automaker chiefs in Michigan this week. Trump is set to visit an autonomous vehicle testing facility in Willow run on Wednesday around mid-day and meet with chief executive officers of several U.S. automakers who want the rules revised. A White House official confirmed Trump plans to visit Michigan, but did not immediately give details.