A senior JI leader speaking from Mansoora, the party's headquarters in Pakistan's Punjab region, told CBS News that the agreement which was signed this month "makes us accept finally and formally that China's internal affairs are not our business."
While confirming the JI's agreement with the Chinese Communist Party, one senior Pakistani intelligence official who spoke to CBS News on condition of anonymity said, "This is a major event for Pakistan and for China. It formally ends what I consider a very bad chapter in Pakistan's relations with China."
Western diplomats said the news confirms the success of China's quiet diplomacy through contacts made with Pakistan's Islamic politicians at different levels, wooing them to back Beijing's position.
A Western official from a European NATO member country said that the agreement "forces us to think if the Chinese are much more sophisticated than what we know. We (Western countries) are still not absolutely certain how far to go in negotiating with people like the Taliban, and China may already be moving in this direction."
In the short term, there is no indication how the agreement might change conditions on the ground immediately. Little is known about current security conditions in the Xinjiang region where Muslim separatists in the past have waged an independence movement.
However, China has kept the region isolated from other parts of the country, making it impossible for outsiders to travel there for independent verification of conditions.
In the past, Chinese officials have complained to Pakistani government officials about reports of activities by Pakistan's Islamists, eager to link up with Muslim separatists in Xinjiang. Pakistan has taken up the issue quietly with its own Islamic leaders on a number of occasions.
The government in Islamabad has been especially worried that such activism may undermine the country's relations with China, which has been Pakistan's most reliable supplier of defense hardware. In the past, Western officials have investigated reports of China's supply of essential components which were used for Pakistan's missile development program.
Since the 9/11 terrorist attacks, Pakistani intelligence officials have reported the participation of Chinese Muslim separatists in operations carried out by al Qaeda and the Taliban in the Pak-Afghan region. The senior Pakistani intelligence official who spoke to CBS News said the number of such Chinese militants "may not be more than in the tens," but added, "It is just not possible to be exact."
By CBS News' Farhan Bokhari reporting from Islamabad