US inventories at the wholesale level posted a month-on-month gain in July, while wholesale sales registered a slight decline, the US Department of Commerce said on Wednesday.

Inventories at the wholesale level rose 0.7 percent from the revised June level to $485.2 billion in July, and were up 5.3 percent from a year ago.

Sales at the wholesale level fell 0.1 percent in July from the previous month to $402.4 billion. Compared with the level of a year ago, the sales were up 2.7 percent.

Declining sales could be a troubling sign for the weak economic recovery, as personal consumption accounted for about 70 percent of the total economic activity in the world's largest economy.