In a week when much of the attention has been on Pakistan securing controversial support from China in the way of two nuclear reactors, Islamabad has announced a significant stepping-up of its cooperation with Beijing on tackling terrorism — one of the few areas where the “all-weather” friends have not always seen eye to eye.

The two countries on Thursday announced they will conduct a joint terror drill to coincide with the sensitive one-year anniversary of deadly riots in China's far western Muslim-majority Xinjiang region, which borders Pakistan. The drill, named “Friendship 2010”, will be conducted between July 1 and 11 in north-western Ningxia Hui Autonomous Region, officials at China's Ministry of Defence said.

While the joint terror drill will be the third of its kind, it has assumed particular significance because of its timing. Thursday's announcement followed last week's visit to Beijing of Pakistani General Ashfaq Parvez Kayani, during which the two countries reaffirmed their strategic and security ties. The Pakistani General is understood to have pledged greater support to China in tackling terror, though his visit was overshadowed by attention on China's controversial agreement to set up two nuclear reactors in Pakistan.

The terror drill in Ningxia will also take place against the backdrop of heightened security in Xinjiang, as the region prepares to mark one year after the worst ethnic unrest in the People's Republic of China's history. Violence between the native Uighur ethnic group and majority Han Chinese claimed more than 200 lives and left 1,700 injured on July 5 last year. In recent weeks, the Chinese government has tightened security in the capital city Urumqi and in Kashgar in the far west, residents in both cities told The Hindu in telephone interviews.

On Thursday, officials in Kashgar said they had broken up a cell of the separatist East Turkestan Islamic Movement (ETIM), which has been blamed for attacks on a police outpost in Kashgar in 2008 killing 17 people and on hotels and offices in Kuqa.

In the past, Beijing has also voiced concern over links between the ETIM and groups in Pakistan, and has called on Islamabad to do more to clamp down on groups operating on its soil.