Asian stocks erased early modest gains on Tuesday, while the euro steadied but remained vulnerable after overnight comments from the European Central Bank chief heightened expectations of easing steps in the euro zone. MSCI’s broadest index of Asia-Pacific shares outside Japan dipped about 0.1 percent, after opening higher, as investors locked in profits following its rise to a one-year high on Monday. Japan’s Nikkei stock average (.N225) was a regional standout, adding about 0.9 percent after marking its highest intraday level since early April.