 Complete the following phrase:  There have been numerous attempts to improve the relationshipnotably, the Shimla summit, the Agra summit and the Lahore summit. Since the early 1980s, relations between the two nations soured particularly after the Siachen conflict, the intensification of Kashmir insurgency in 1989, Indian and Pakistani nuclear tests in 1998 and the 1999 Kargil war. Certain confidence-building measures  such as the 2003 ceasefire agreement and the DelhiLahore Bus service  were successful in de-escalating tensions. However, these efforts have been impeded by periodic terrorist attacks. The 