The Bank of Japan's (BOJ) efforts to reach its 2 percent inflation target didn't get much of a boost from the latest data, with the country's core consumer price index for June barely budged and as households unexpectedly snapped their wallets shut.

Japan's core consumer price index (CPI), which excludes fresh food, rose 0.1 percent on-year in June, a tad above the 0.0 percent forecast in a Reuters poll. The "core-core" CPI, which excludes both food and energy prices, rose 0.6 percent from a year earlier.