BEIJING -- Imported iron ore prices stayed unchanged in the week ending on July 9 from the previous week, as steel factories and traders lacked impetus for purchases amid a sluggish steel market, according to the Xinhua-China Iron Ore Price Index released Tuesday.

The price index for 63.5-percent-purity iron ore imports stayed at 139 points, while the price index for 58-percent-purity iron ore imports also remained unchanged at 118 points, according to the index, which is compiled by Xinhua News Agency to track iron ore inventories and imports on Chinese spot markets.

However, stockpiles of imported iron ore at 25 of China's major sea ports rose to 97.91 million metric tons, up 450,000 tons from a week earlier.

The nation's steel prices have taken a dive since the start of the year, which has weighed negatively on demand for iron ore imports.

The country's economic output expanded 8.1 percent in the first quarter of the year, marking the slowest growth in almost three years. Statistical authorities are scheduled to update economic growth data for the second quarter on Friday, with analysts expecting a growth rate of 7.5 percent.

China customs said Tuesday that exports rose 11.3 percent year-on-year to $180.21 billion in June, slowing from 15.3 percent in May. Imports increased 6.3 percent to $148.48 billion, also down from the 12.7-percent growth registered a month earlier.