VATICAN CITY (Reuters) - Pope Francis urged U.S. President Donald Trump to be a peacemaker at their highly anticipated first meeting on Wednesday, and Trump promised he would not forget the pontiffs message.

Under clear blue skies, Trump, who exchanged sharp words with the pope during the U.S. election campaign last year, received a tribute from the Swiss Guard in a Vatican courtyard when he arrived to meet the pope.

Trump entered a small elevator taking him to the third floor of the Apostolic Palace and, after a long ceremonial walk past frescoed corridors, shook the popes hand at the entrance to the private study, which the frugal pope uses only for official occasions.

Francis smiled faintly as he greeted Trump outside the study and was not as gregarious as he sometimes is with visiting heads of state. Trump, seeming subdued, said it is a great honor.