The 35-year-old signed a one-year, $31-million extension to stay with the Raptors through the 2020-21 season in October 2019, as he entered the final year of a three-year, $100-million deal.
Lowry helped Team USA to a gold medal at the 2016 Olympic Games in Rio.
Earlier Tuesday, Jrue Holiday and Khris Middleton of the Milwaukee Bucks as well as Kevin Love of the Cleveland Cavaliers reportedly committed to the U.S. men's senior national team.
They'll join Bam Adebayo of the Miami Heat, Kevin Durant of the Brooklyn Nets, Draymond Green of the Golden State Warriors, Bradley Beal of the Washington Wizards, Jayson Tatum of the Boston Celtics, Devin Booker of the Phoenix Suns and Damian Lillard of the Portland Trail Blazers.
Brooklyn’s James Harden has also committed to play for Team USA, though there is concern over whether his hamstring injury — which sidelined and slowed him at times during the Nets’ post-season run — will actually allow him to be part of the team.
— With files from The Associated Press