Japan is seeing the return to core inflation for the first time since December 2015.
Consumer prices – including oil but excluding fresh food – rose by 0.1 per cent in January compared to last year.
The rise was in contrast with a median market forecast for flat growth, according to Reuters, and followed a 0.2 per cent drop in December.
Energy prices were behind the increase, with petrol prices jumping 9.2 per cent over the year.
The expectation is that the Bank of Japan is getting closer to its 2 per cent inflation target, following the global recovery in commodity prices and the decline in the yen since the election of Donald Trump.
Headline consumer prices were up by 0.4 per cent compared with the same period last year, a marginal increase on the 0.3 per cent seen in December 2016.