Tensions between China and the U.S. have escalated yet again after Beijing refused a U.S. Navy request for a port visit to Hong Kong, hours before a top Chinese official accused Washington of putting “a knife to China’s neck” with its latest round of trade tariffs. China denied the amphibious assault ship USS Wasp a port visit to Hong Kong and also recalled Vice Adm. Shen Jinlong from a visit to the U.S., calling off a planned high-level naval meeting. Chinese officials didn’t offer an explanation for refusing the port visit, but it came shortly after the countries hit each other with huge tariffs. “Now that the United States has adopted such a huge trade restriction measure... how can the negotiations proceed? It’s not an equal negotiation,” said Vice Commerce Minister Wang Shouwen on Tuesday. U.S. tariffs on $200 billion in of Chinese goods and retaliatory taxes by Beijing on $60 billion in of U.S. products kicked in Monday.