MILAN (AP) — Youth climate activists Vanessa Nakate and Greta Thunberg have chastized global leaders for failing to meet funding pledges to fight climate change and for delivering too much “blah blah blah’’ as climate change wreaks havoc around the world. Four hundred climate activists from 180 countries were invited to Italy’s financial capital of Milan for a three-day Youth4Climate summit that will send its recommendations to a major United Nations climate summit in Glasgow that begins Oct. 31. But the participants in Milan on Tuesday were demanding more accountability from leaders and a bigger official role for young people at the U.N. climate summit.