Hu Jintao became General Secretary of the Communist Party of China in late 2002, succeeding Jiang Zemin as "de facto" paramount leader of China. Hu continued to insist that talks can only proceed under an agreement of the "one China" principle. At the same time, Hu and the PRC continued a military missile buildup across the strait from Taiwan while making threats of military action against Taiwan should it declare independence or if the PRC considers that all possibilities for a peaceful unification are completely exhausted. The PRC also continued applying diplomatic pressure to other nations to isolate the ROC diplomatically. However, during the 2003 Iraq war, the PRC allowed Taiwanese airlines use of China's airspace.