Warsaw: Polish troops were to have occupied West Germany in the event of a nuclear attack by the Warsaw Pact on western Europe, according to previously secret files made public in Poland Wednesday.

The plans were contained in 1,445 files about the Warsaw Pact — the military alliance of the Soviet bloc which disbanded in 1991 — handed Wednesday by the defence ministry to Poland's National Remembrance Institute, a body with charged with investigating Nazi-era and Communist-era crimes.

Under the plans, Polish troops were to “occupy German territory in several days, particularly German towns destroyed by a nuclear attack and exposed to strong radioactivity,” deputy defence minister Aleksander Szczyglo said.

Up to half a million Polish soldiers were to take part in the military operation. They were to reach the French border in six days. Some 40 percent of Polish troops were expected by military experts to be either killed or injured.

One version of the plan, which was in force from the 1960s, was personally approved in 1976 by Poland's communist leader at the time, Edward Gierek, according to defence ministry officials.

Officials from the defence ministry and the National Remembrance Institute Wednesday also showed reporters a Polish plan of “aggressive operations” dating from 1980 which envisaged the use of 194 short-range tactical nuclear warheads.

“It's an operational plan which, fortunately, was never carried out,” said the institute's president Janusz Kurtyka.

“But these documents allow us to deepen our knowledge of the Warsaw Pact,” he added.

Defence minister Radoslaw Sikorski decided in January to make public Poland's secret Warsaw Pact files. However, 73 files still considered sensitive will be kept secret. Signed in the Polish capital in 1955, the pact grouped Moscow and its satellite states of Bulgaria, Czechoslovakia, East Germany, Hungary, Poland and Romania in a military alliance to counter the perceived threat of NATO.

It was finally dissolved in 1991 after the collapse of communism in the region.