Relations between the world's two fastest-rising superpowers are suddenly as chilly as their snowy mountain border, with China and India trading blows in a high-stakes verbal war.

Border tensions between the two nations are inflamed, the disagreement over disputed territory that China calls “southern Tibet” and which India governs as its state of Arunchal Pradesh. Each country claims huge chunks of the other's territory along the 3,500-kilometer Himalayan boundary in a dispute that stems from their brief war in 1962.

India reports a sharp rise in Chinese “incursions” into its territory over the past 18 months, which has prompted new troop deployments and upgrades to fortifications.

In Beijing, meanwhile, hostility to India has risen in the state-run media in recent weeks, with the People's Daily calling India “narrow-minded,” accusing it of “provocations” and adding that “India turned a blind eye to the concessions China had repeatedly made over the disputed border issues, and refused to drop the pretentious airs when dealing with neighbors like Pakistan.”

“This level of harsh words between two sides has never happened in the past,” said Sun Shihai, dean of South Asian culture at the Chinese Academy of Social Sciences.