Former Polish President Wojciech Jaruzelski has apologised for the first time for the role he played in the 1968 Soviet-led invasion of Czechoslovakia.
Gen Jaruzelski offered his "sincere apologies"
Gen Jaruzelski, 82, said he was still "tormented" by the decision to send in Polish troops to crush a pro-democracy movement, known as the "Prague Spring".
He made the apology on the 37th anniversary of the invasion on the Czech television.
Gen Jaruzelski was Poland's minister of defence at the time.
"It was a stupid political act," he said during a TV debate on the issue.
"Today I deeply regret it but at the time I could not act otherwise. It was a political decision.
"But, in 1968, I was the defence minister implementing a political decision, convinced that there were grounds for that on the basis of the information available to us then," Gen Jaruzelski said.
Warsaw Pact invasion
Dozens of people were killed in a massive military clampdown in the then Czechoslovakia by five Warsaw Pact countries.
Soviet tanks remained in Czechoslovakia until 1991
Several members of the liberal Czechoslovak leadership were arrested, including Prime Minister Alexander Dubcek.
The occupation was launched in line with Moscow's policy of the time that military intervention was justified to enforce compliance from the Soviet Union's satellite states.
Soviet troops remained in Czechoslovakia until 1991, two years after the so-called "Velvet Revolution" overthrew communism.
In 1993 Czechoslovakia completed "Velvet Divorce" which resulted in two independent countries, the Czech Republic and Slovakia.