Chinese President Xi Jinping has brought Japan's wartime atrocities back into the spotlight by reasserting that Imperial Japanese troops killed more than 300,000 people when they occupied Nanjing in 1937.

In a speech Friday in Berlin, Xi also said that more than 35 million Chinese were killed or wounded by Japan's aggression, which stemmed from militarism.

Xi's remarks are likely to draw fire from Japan as Tokyo and Beijing continue to spar over the death tally from the Nanjing Massacre. Chinese experts on a bilateral panel of historians set up in 2010 concluded that over 300,000 people were killed, while their Japanese counterparts capped the tally at 200,000. Other estimates go as low as 20,000.

This and other historical disputes are still straining bilateral ties that were recently damaged by the ongoing sovereignty row over the Japan-controlled Senkaku Islands.

Xi responded to criticism of China's growing military budget by saying that it is proportionate to the country's size, and that Beijing's aim is to prevent itself from ever again being oppressed or colonized by foreign powers.

On March 5, China announced a 12.2 percent rise in military spending to 808.23 billion yuan for this year.