WARSAW -- Sirens wailed through the Polish capital on Monday and traffic halted to commemorate the 1944 Warsaw Uprising against Nazi occupation and honor the 200,000 victims of one of World War II's bloodiest battles.


Pedestrians also stood at attention in silence at 5 P.M. as the sirens marked the exact start of the 63-day battle 50 years ago in which Warsaw was all but destroyed.


Thousands of flags fluttered on buildings across the city and hundreds of veterans attended a Mass for the victims.


President Lech Walesa paid solemn tribute to the dead but also told foreign leaders, including German President Roman Herzog, U.S. Vice President Al Gore and British Prime Minister John Major, it was time to bury past hatred.


"Our societies' histories are bound by a tragic knot. We have to overcome our past, to learn a lesson from it. We must look towards the future," he said, hosting a lunch for the foreign dignitaries in his presidential palace.


"The order that has prevailed for over half a century has been spent. It must be replaced with a different one, a better one, an order which will allow us to live as one family."


Later, Herzog, in a speech delivered in front of a huge monument to the uprising, apologized for the suffering Germany had caused Poland during World War II and for its brutality in putting down the rebellion.


"Today I bow down before the victims of the Warsaw Uprising as before all Polish victims of the war. I ask for forgiveness for what Germans did to you," he said.


The outgunned insurgents, who began the uprising on Aug. 1, 1944, were forced to surrender by Oct. 2 without achieving their aim of taking control of Warsaw before the Soviet army arrived and established Communist rule.


Soviet troops stood immobile east of Warsaw as the Germans pummeled and starved the insurgents into capitulation.


Poles regard the uprising as a heroic struggle for their homeland, even though it failed to prevent almost half a century of Soviet Communist domination. It has helped shape their thinking ever since.


"The Warsaw Uprising has a key importance to the Europe of the second half of the 20th century," Polish-born Pope John Paul said in a message read out on his behalf at the outdoor Mass attended by Walesa and uprising veterans.


"It was the beginning of the process of shaping independent states in central and eastern Europe which could be fully carried out only in 1989 after the collapse of the totalitarian systems," he said, referring to the end of Communist rule.