By Karen Lema MANILA (Reuters) – U.S. Vice President Kamala Harris will reaffirm American commitments to the defence of the Philippines when she meets with President Ferdinand Marcos Jr. in Manila on Monday, a senior U.S. administration official said. Harris, whose three-day trip to the Philippines includes a stop on the islands of Palawan on the edge of the South China Sea, will also reaffirm Washington’s support for a 2016 international tribunal ruling that invalidated China’s expansive claim in the disputed waterway. “The vice president will underscore our commitment to stand up for the int…