Two envoys who represented the Dalai Lama in failed talks with China on Tibet issues have resigned to protest Beijing's unwillingness to consider new autonomy measures for the Himalayan region.

The exile Central Tibetan Administration in northern India announced the resignations Monday, saying envoys Lodi Gyari and Kelsang Gyaltsen left their posts last week. The two diplomats held nine rounds of talks with Chinese officials in the past decade, without making notable progress.

A CTA statement said the envoys earlier voiced their frustrations over a lack of “positive response” from Beijing to a series of initiatives aimed at easing tensions in Tibetan Buddhist areas of southwestern China.

In their resignation letter the envoys cited “the deteriorating situation” inside Tibet since 2008, saying tensions spawned since then by China's crackdown on protests has led to several self-immolations by Tibetans opposing Chinese rule. The letter also cited a 2008 autonomy proposal to Beijing and a 2010 memorandum, saying Beijing did not respond to either communication.

Beijing insists Tibet is a non-negotiable part of China, and has sought to win over the Tibetan plateau's far-flung population by investing in infrastructure projects as well as health and welfare initiatives.

But many residents resent what they consider a Chinese intrusion into Tibetan cultural and religious practices. Tibetan leaders say those intrusions threaten the very existence of Tibetan Buddhism and warn that Chinese interference will continue to spawn self-immolation protests that have rocked the region for the past 15 months.

Nearly 40 people, including Buddhist monks, nuns and their supporters have set themselves on fire in protest of Chinese rule since March 2011. Witnesses say many of them also called for the safe return of the Dalai Lama as they set themselves ablaze.