BEIJING, June 12 -- China's producer price index (PPI), which measures costs for goods at the factory gate, saw a significant narrowing in its year-on-year decline in May, with a drop of 1.4 percent compared to a 2.5-percent decrease in the previous month, official data showed Wednesday.

The National Bureau of Statistics (NBS) attributed this to rising international commodity prices and improved supply-demand conditions in the domestic market of industrial goods.

On a monthly basis, the PPI edged up 0.2 percent in May, reversing a decline of 0.2 percent a month earlier and ending a six-month streak of continuous decreases, the data showed.

Among major industries, China's coal mining and washing industry saw a 0.5-percent month-on-month price increase, driven by tight supply in major coal-producing regions and a surge in demand as power plants restock ahead of peak summer usage.

Prices in ferrous metal smelting and pressing industry rose by 0.8 percent month and month, bolstered by favorable market expectations due to the country's large-scale equipment upgrades.

The non-ferrous metal smelting and pressing industry saw prices rise by 3.9 percent month on month, driven by higher international market prices.

China's consumer price index (CPI), a main gauge of inflation, was up 0.3 percent year on year in May, NBS data showed.