SHANGHAI — China’s state-run news media warned Washington on Friday not to “recklessly practice militarism” or engage in “war mongering,” a day after the Obama administration outlined a new military strategy with an increased focus on China.

The sharply worded commentary, published by the official Xinhua News Agency, also urged the United States to play a constructive role in the region.

President Obama introduced a new defense strategy on Thursday, aimed at creating a leaner, more dynamic American fighting force with an enlarged presence in Asia and the Pacific.

Although the administration is seeking to trim hundreds of billions of dollars from the Pentagon budget, the president and Defense Secretary Leon E. Panetta have said the United States will shift resources to the region because of its growing economic and military significance.