Pakistan "issued" permission to foreign tourist without Indian consent when that area was not demarcated. And RAW found out, PA was procuring the high altitude gears from one company in London, which incidentally, was the only company supplying sophisticated equipments. This sowed a doubt in IA, and we see the results.
Had Pakistan not tried kargil, Siachen might have be demilitarised now, with tourist from both countries enjoying the benefit. Its really tough to imagine the life of Indian soldiers there. Its a hell.