WASHINGTON — President Trump placed a “warm” phone call to Philippines President Rodrigo Duterte, who has been widely criticized for a bloody anti-drug crackdown, and invited him to visit the White House, both countries said. A White House statement late Saturday said the conversation between the two leaders was “very friendly,” and added that the U.S.-Philippine alliance was “heading in a very positive direction.” In the Philippines, a presidential spokesman said Trump expressed understanding of challenges facing Duterte, “especially on the matter of dangerous drugs.” Human rights groups have expressed deep concern over Duterte’s harsh methods against suspected drug users and drug dealers.