By Arshad Mohammed NEW YORK (Reuters) - The Japanese military could expand its role and missions around the world under new U.S.-Japan defense guidelines that are expected to be released on Monday and may cause unease in China. A centerpiece of Japanese Prime Minister Shinzo Abe’s U.S. visit this week, the guidelines are part of Abe's wider signal that Japan is ready to take more responsibility for its security as China modernizes its military and flexes its muscles in Asia. The conservative Japanese leader, who is scheduled to meet U.S. President Barack Obama on Tuesday, will likely want fresh assurances that America will come to Japan's aid if necessary in a clash with China, Japanese politicians and experts said. The current guidelines focus on the defense of Japan and on "situations in areas surrounding Japan" -- widely interpreted as a possible conflict on the Korean Peninsula -- where Japan's military is relegated to giving U.S. forces "rear-area support." The new guidelines are likely to expand the geographic scope of cooperation and to include areas such as cybersecurity and counter-terrorism, according to a recent article by Adam Liff, a fellow at the Princeton-Harvard China and the World Program.