Soviet troops stationed in Poland have held joint exercises with Polish Army units, the official news agency PAP announced. It said the exercises were designed to perfect military readiness of units from both armies. The announcement of the maneuvers coincided with mounting tension in Poland over strikes threatened this week and forceful restatements by Polish leaders of their country's tight alliance with the Soviet Union. Polish television showed a four-minute film clip of the exercises on the evening news program. It showed helicopter gunships, jet fighters, tanks, rockets, and amphibious vehicles in action.