China’s envoy to India has warned that a military stand-off along a contested part of the border in the Himalayas was the most serious confrontation between the two nations in more than 30 years. Ambassador Luo Zhaohui told media in New Delhi that the Chinese people were deeply angry over the “occupation” by Indian troops of its sovereign territory but said the showdown should be resolved through diplomatic means. Each side has about 3,000 soldiers facing off across a remote plateau in the pocket of land where Tibet meets Sikkim and Bhutan, Indian media reported citing army sources. Last month China began building a road on territory also claimed by Bhutan, a move seen as upsetting the status quo, according to the South China Morning Post. Although China and Bhutan have spent decades negotiating the precise border without serious incident, the tiny Himalayan kingdom sought help this time from its long-time ally, India, which sent troops onto the plateau.